Archive of Our Own ^beta

Chapter Text

"If you make weapons of science, and revive the older generations, they'll begin fighting over established interest, and we'll be right back in a tainted world." Tsukasa said, his face expressionless, as he imagined guns, wars, hate crimes, refugees, and people dying of preventable diseases, like she probably did, encased in stone, alone. "I don't mind getting my hands dirty to prevent that."

"I have one question for you." Senku's manic grin was close to faltering. "Is one of the worst things about a tainted world people dying of preventable causes?"

"I suppose it is, the image I had in my head was a modern war, but I know too much of sickness for it to be left out" Tsukasa looked genuinely intrigued, watching a far from genuine Senku. "A mighty world of the young will lack anyone to prevent another from getting something they need."

"What if someone needs antibiotics?" Senku's grin felt far less forced now. "What happens when people don't manage to catch chickenpox when they are still young? What happens to the chronically ill? Taking care of them without science will be inefficient and unworkable. You don't want the bravest of us to starve." Senku was honestly very intrigued to hear what Tsukasa would say in response. "And you won't let those under you die. You aren't logical enough to let people die when they're too much work, or ready to be a eugenicist in pursuit of an actually perfect people. You want to play a civilization building game as much as I do, strongest primate."

"The only alternative is death or loss of freedom under the tyranny of a modern state, and I don't want to go back to billionaires." Tsukasa thought for a minute, the ignored Yuzuriha shaking, but she noticed Tsukasa's grip loosening as he calmed down. Tsukasa looked back at Senku. "I suppose the evil Tsukasa Empire you're imagining lacks all science. Anything other than force equalizers that doesn't make it too easy to make them would be permitted. I have no intention of letting people starve. A strong enough people will feed themselves through any winter, and jarring foods, or even herding beasts, would not give anyone undue power, so long as things of such advancement are communally owned. Thus why we can never resurrect everyone, you can't hold small objects in common with a billion people, or even a few thousand. I'm afraid we've gotten quite off topic, I believe you failed to clarify the recipe for revival fluid last we met?"

"So you'd accept a socialist, decentralized state with gun control?" Senku blurted out. Tsukasa blinked. Yuzuriha starred at Senku.

Yuzruriha struggled and yelled "Senku you never proposed a compromise ONCE? How stupid can you be you BIG OAF!" And then Tsukasa pulled her back "I'm afraid your struggling cause you to cut your neck on my blade a little. I don't recommend getting cut. As Senku mentioned we don't have any antibiotics. And Senku isn't that big or oafish."

"So would you be okay with a form of socialism? You know very well how little I care about politics, so long as no one dies." Senku was hopeful.

"Do you have any clue how hard it would be to prevent anyone from making guns if we had a modern technological level?" Tsukasa was wary of this plan, he knew people would always find a way to misuse what is given to them. "And we still couldn't run around reviving older generations, they would never give up power."

"Well, when a society is fully formed, numbers become a force multiplier. A lone person with a gun isn't dangerous unless it's fully automatic and no one stops them before they decide to do a massacre. An incredibly popular person with guns isn't much more dangerous then one without. And guns won't be easy to make until we get to that point. Also I never said I want to revive people indiscriminately, I mean look at who I've revived, my friends and you, to kill lions. Just eventually we'll get to the old people, agreed?" Senku wasn't doing any evil plots. He wasjust trying to leave politics to the political.

"Will you promise to never make weapons of science yourself, except as a last resort, and to prioritize a stable society over scientific progress?" Tsukasa handed Yuzuriha a cloth to wipe the blood off her neck and let her go, but still held the blade near her.

"You know I can't prioritize anything over science." Senku's confidence in a diplomatic solution faltered.

Tsukasa grabbed Yuzuriha's shoulder and said "I knew you wouldn't lie about science. I can't make a deal without such a promise though."

Senku though for a second, and then lit up. "Well long term having a society on my side would be good, so what if the society is oriented primarily towards science, right after staying good and unsullied or whatever. Then I get motivated to protect the society enough that I might even science-y slow down growth to help it!"

"Hm, I get to be in char-"

"LET GO OF YUZURIHA!!" Taiju screamed at what was probably close to the top of his lungs, but knowing him his limit would somehow be higher. He was charging towards Tsukasa, arms full of sticks.

"Okay, slow-" Tsukasa let go of her arm and raised his weapon away from her right as Taiju reached him, chucked the sticks haphazardly at the fire, picked Yuzuriha up, placed her next to Senku, and arranged Tsukasa and himself to resemble how he was holding Yuzuriha. "...to late for that I guess."

"You can do what ever you want to me, but you can't hurt anyone else!!" It was apparent that Tsukasa was letting him do this when he tried to push Tsukasa's blade to his throat and totally failed to move his hand.

"Taiju, back off, I'm not killing anyone unless the deal with Senku falls through, and then we can try to figure out how that's a deal of any kind." Tsukasa stepped away from Taiju and turned back to Senku, who was staring at the horizon. "Did you start those fires?" He asked Senku after following his gaze.

"No. Tsukasa, we think those are smoke signals that responded to our gunpowder accidentally blowing up." Senku turned around and started throwing the sticks Taiju threw badly into the fire. "That means someone else was revived before us. I need you to swear if they're capitalist pigs or whatever you fear you won't commit a genocide, or if there's only a few you'll find some nonviolent way to get them on out side."

Tsukasa took a deep breath. "No."

"I would very much prefer not to potentially loose my life blowing you up." Senku said, as Taiju took a defensive stance.

"I also prefer not killing you. I can promise the later. And I will avoid genocide if possible, but a pure society cannot exist if there's a false one over the hill."

"Well I can't live with a genocider. That's the actual term by the way, heh." Senku said.

"In English too?" Tsukasa couldn't help having a conversation with this man, he held no concept of emotional weight, and loved facts so much he couldn't help dispensing them.

"Yep!" Senku chirped. "So the deals off until we figure out if you're committing genocide or not?"

"I can work with that. If the people or person is amicable we'll form a combined state with the number one goal of making a stable, pure society, though this is to facilitate scientific progress without the downsides, and you'll agree to both not make weapons of science and let me be the head of state?"

"I don't like slowing down science, but I think I can work with that."

Tsukasa sighed. "I hope we can work together. You're a smart man Senku. Now take out that gunpowder and pour it in the spring."

Senku grumbled and poured it out. "I made scientific progress with that..."

"So we're friends?" Taiju asked.

"Unless he does a genocide." Senku shrugged.

"We're heading out to find the person who made the smoke signals then?" Yuzuriha asked, packing up the gear. "I'm Yuzuriha by the way!" she said, standing up and revealing the bloody scratch on her neck.

"I'm Tsukasa, sorry about that cut." Tsukasa didn't really feel at fault for the incident, that girl needed therapy.

They all began to walk. 'A very narrow success, perhaps. Not optimal, but not bad, per se.' Tsukasa and Senku both thought.

Chapter Text

No one talked the whole way, and it was quite tense. Eventually they found the fires. They were slightly spread out, so the smoke would be distinct, and there were really no other markers of people. Eventually Yuzuriha found a big dent in some soft earth, which was round and looked like something heavy had been placed there. Senku found some strange equally circular footprints, which probably weren't made by whoever they were looking for, but weren't very natural looking and they had no other leads. They started walking again, as quiet as before. Tsukasa looked like he was going to ask something, but stopped.

"Senku, do you see that?"  Tsukasa motioned to a branch.

"Is that... fabric?"

"We're going the right way?!" Taiju exclaimed.

Yuzuriha was inspecting it. "It's not fabric, it's hide, and it's hand-stitched, but if it's someone who was resurrected they've either been awake for years or a fellow crafts club member, 'cause it's quite well stitched."

"Huh, a win for the Kingdom of Science?" Senku hummed. "Skilled workers are essential to manufacturing basically everything higher on the tech tree than uh... no it's just useful to have skilled workers, everything needs more skill than we've got, that crossbow was terrible."

"Win for the Kingdom of Science indeed, people wearing hide clothing are most likely not wielding weapons of science. This doesn't rule out some odd precapitalism though." Tsukasa then began to wonder what they'd call their new state, as he began to consider weather they'd make a republic, unity state, or federation he spotted a movement about a half-kilometer ahead of them. "I saw something, everyone run, follow the tracks." And with that he took off. Taiju sprinted forward at full speed, slightly slower than Tsukasa, while Senku and Yuzuriha trailed behind, not putting any less effort in, but they were just slower.

Before it could be reviled weather Taiju's stamina would eventually allow him to catch up to Tsukasa, they both stopped, the tracks nowhere to be found. Yuzuriha caught up and started looking for clues. "If there's no one does that mean they're corrupted and Tsukasa will kill them?" Taiju asked, right as Senku finally caught up (his stamina was pretty much the antithesis of Taiju's).

"If no one's here I won't have anyone to kill and we'll just join forces anyw-" Tsukasa's explanation was interrupted by a shape dropping out of the trees and kicking Taiju fiercely on the head, making him fully stumble, suggesting is was a nearly lethal blow. The shape, now clearly a girl, still in midair, spun around and stabbed at Tsukasa with large flint blades. Tsukasa was, however, alerted by the girl attacking Taiju first, and knocked both blades out of the way with his.

"YOU CAN'T KILL ANYONE IF I KILL YOU FIRST!" She yelled, landing, blocking Tsukasa's counterattack, and kicking him in the face.

"Ow. Well no one wants to kill anyone, aside from you it seems." Tsukasa began parrying her constant attacks, and driving her back with the shear power of his occasional counterattacks.

"Hey Yuzuriha, these footprints are about fifty-four percent deeper than the ones she just made, weird shoes either way, but they shouldn't make prints of varying depth in the same mud." Senku said, on all fours, in the middle of a combat scenario.

"That's what you're thinking about?!" Yuzuriha gasped, and tried to pull him away from the combat.

"If a centimeter is about this big, and she weighs say, 50 kilos, then she was carrying- up to 40 more kilos." Senku finally stopped resisting Yuzuriha and slid across the mud, dragged by his ankles as Taiju blocked both sides' lethal attacks, getting smacked by both for interfering quite a bit. "Yuzuriha, help me find whatever she's carrying!" Senku said, squirming out of her grip and charging through the fighters' very stabby area of the clearing.

"Senku! Goodness and I thought I was- whatever might as well help him." Yuzuriha grumbled, and then ran over to the trees near where the battle started. "Found it!" She yelled, causing Senku to charge in between Tsukasa and the girl to get back, only surviving cause Taiju threw him over his head out of the way of one of the attacks. "It's a big pot. Don't see why you're so interested in it, Senku." She said, pointing at a big pot nested in the tree.

"Huh, same size at that circular hole from earlier. Looks like we got the right person." Senku said, ignoring Yuzuriha. "HEY! STABBY GIRL! I'LL SMASH YOUR BIG POT IF YOU DON'T SURRENDER!"

"No! I'l-" She turned around and was immediately punched in the jaw by Tsukasa, knocking her out instantly.

 "Senku? This girl can't be a first generation revivee." Tsukasa said, picking her up, looking at her funny, and then searching around for some rope.

"While it doesn't sound likely I'm sure mixed people can get revived same as Japan- ohh, wait yeah, you'd recognize any martial artist as strong, as, well, much stronger than a lioness, comparing how long it took you to beat both." Senku thought about it for a second. "Are her skills like, totally one billion percent unachievable as a revivee of only a few years with some martial arts training, or is it like raised by martial artists as a hunters minimum, or is it just inhuman, or what?"

"Impractically good. Would take a least a decade for anyone normal to learn. Wouldn't matter if she was revived ten years ago or was born in this stone world, but either way it's impressive."

"Was she in any way mentally unstable? I didn't notice anything but social skills are not my strong suit." Senku realized there might be a whole kingdom, waiting to become a scientific one. With any luck (also not Senku's strong suit) they'd have a stone age economy and either a horizontal distribution of power or a single dictator he could let Tsukasa kill with some irrational righteous fury.

"Nope." Tsukasa said.

"I didn't think her attachment to the jar was anything crazy, she seemed much less passionate about it's survival than "anyone"'s survival." Yuzuriha said, she thought a bit, then started talking again just as Senku did. "Senku were you- oh sorry I interrupted you!"

"It's okay, go ahead." Senku said.

"Uh, well, Senku were you proving to yourself she isn't alone and is part of a moderately sized society?"

"Yep! And it's most likely she is!" Senku said, grinning.

"Hmm. We don't want to get on a whole society's bad side, we'll have to get her somewhat alright with our existence at least." Tsukasa said.

"This is heavy." Taiju said, carrying the pot out of the tree.

"Guys." Yuzuriha said, looking pail. "Taiju doesn't call things heavy."

"Goodness." Senku said, looking like this was quite a funny situation. "Perhaps I underestimated it's weight. I heard sloshing, is it water?"

Tsukasa opened, the lid, confirmed, they lifted it himself. "Can also confirm it's weight. Very, very heavy. Not sure either of you could do much more than knock it over."

The girl woke up. "What have- hm. I'll kill you all."

"Significantly more fierce than a lioness." Tsukasa said. "I'm terribly sorry for tying you up, I was simply afraid you were trying to kill these fine people, and I wouldn't accept that without good reason."

"I had good reason, ratbasterd." She said, spitting on the ground, and then leaping to her feet, tottering around with her feet still tied together.

"What were they, might I ask?" Tsukasa said.

"You were talking about killing. 'If no one's here then there's no one to kill' or something. Murdering the corrupted. I don't care how good of a reason you've got, I'll kill you for that."

"So what you're saying is there are people you'll kill to protect?" Senku said, striding forward like he had a good reason to be lecturing a tied up girl. "What sort of people?"

"Women and children. Old people. You are talking about killing innocents." She spat at Senku.

"I don't see why you keep equating her with a lioness, she's much more of a she-clownfish or an ant warrior." Senku said, his mind spiraling into sex dynamics of different creatures. "If you want to talk about his convoluted reasons for genocide, talk to the one preaching them, I don't plan on killing anyone who doesn't inhibit science." Senku said, gesturing to Tsukasa.

"Scie-?" She squinted, the looked to Tsukasa. "So crazed monster, why would you kill?" The girl said, the fury in her eyes transitioning to distrust.

"I would only kill your people if they are too far gone and hold customs that they won't let go of without their lives, and which irreversibly harm people." Tsukasa said, arms crossed.

"What sort of customs?" She said, squinting with her odd blue eyes.

"Are some people born better than others? Are people told that everything they got was earned by however hard they worked when some have an advantage? Are hereditary advantages protected? Anything like that?" Tsukasa said, his mouth even less smile-like then normal.

"Not really. The priestess is a heard-y position or whatever you called it, but she doesn't carry too much power, and her husband, er, spouse, women have won but I don't know if they married, is the Chieftain, and that's chosen by skill and valor." The girl thought for a second. "And there isn't too much hypocrisy, I mean the current leader is somewhat petty and past ones have certainly been awful, but those aren't customs."

"Doesn't sound like a drop of blood shall have to be spilled." Tsukasa said, slightly smirking for once. "What's your name? Mine's Tsukasa Shishio, I'm an MMA fighter."

"Em em eigh?? I'm a fighter but I'm not an emem."

"...wait how many generations have you been here?" Senku said, noticing how many modern things she'd seemingly missed.

"I'm sure there's a story in the tales about when we got here but not living memory. My name's Kohaku, and em em-san has entirely too many names."

"Mine's Senku, I'm a scientist."

"Kohaku, you're telling me you learned how to fight in this stone world, without knowing what MMA is?" Tsukasa said, aghast.

"Yes." She said, unphased.

"You're either magic, train 10 hours a day, or have the potential of a lesser goddess." He said, again, aghast.

"Thank you?" She said. Then she jumped up, still tied up, landed on the ground next to her blades, and slid past them to cut the ropes off her upper body, then using them to free her feet. "I do train at least five hours a day."

"Hey, where are Yuzuriha and Taiju?" Senku said.

"Over there, the boy one's crying I think." Said Kohaku, gesturing with large blades.

"He just does that." Senku said, glancing over. "I wonder if he confessed to Yuzuriha, that'd be funny."

"Okay?" Tsukasa said, disinterested before he turned to Kohaku. "Kohaku, will you lead us to your people?"

"Nope." She said with a shrug. "You're all crazy and at least one of you was seriously considering murdering all of my people. Bye em em ay fighter, you are a great warrior, and bye scion cyst!" And with that she leapt into the trees, turned around, heaved the massive jar onto her shoulders, climbed up again, and disappeared into the foliage.

"I have to train that girl, she could be unstoppable." Tsukasa said, almost in awe.

"And I need a workforce to get metals and glassware and electronics and, well, most things." Senku said. "I vote we finally shake on our deal and go find these people."

"Okay." Tsukasa said, and they awkwardly shook on it.

"COME ON YOU TWO!" Senku yelled. "We've got a new goal! Rule Kohaku-place!"

"Coming!" Taiju yelled, busting out of the foliage.

"Tsukasa you can probably figure out where she went, right?" Senku asked.

"Sure. Obscenely heavy jar of funny water, uh, thick branches or twisted ones until we get footprints. Won't be too hard."

And the group set off again, slightly more talkative this time.

Chapter Text

Ginro was tired. Kohaku had been late with her spring water today, and warned about four people. A crazed sorcerer, probably weaker than Chrome with funny symbols on his shirt, a cute girl (literally that's all), an inhumanly tough pacifist who prevented anyone from killing anyone, and a warrior the likes of which Magma could only dream of beating, wearing a lion's skin and with an obsidian spear.

Certainly Kinro would make rules of this report. For now the tired guard wouldn't have to think about these, and could instead focus on girls. Girls good. Boob good. Wowcool skin good. Butt good. Ginro wished he had cool hair like Ruri or something, but that'd get in his face when he was fighting and Magma would call him a sissy. He had some deep philosophical thoughts on girls. This was, however, just to fill the time in his head, and eventually when something shocked him out of his daydreaming, he was literally so zoned out he was sort of disappointed when he realized how he was leaning on his spear was simply impossible with boobs meaning he had none, then he gotten a hold of his senses. "Kinro, lion-skin guy was in a tree." And he yawned.

"Hmm. Can't let them in, remember the rules." Kinro said, entirely emotionless but not sleepy at all. A minute later they arrived.

"HEY, GET LOST! NO OUTSIDERS ALLOWED!" Ginro said, brandishing his spear and the four. One really could only be described as a crazed sorcerer, another as a cute girl. Of the other two, both were tall and strong, but one was terrifying and wearing the lion's skin like it was his own, and he would kill anyone who encroached on his territory.

"He's right. No outsiders allowed. Rules are rules. You'll have to leave." Despite not doing a thing with his spear Kinro was probably being twice as intimidating.

"I'm afraid we don't plan on leaving." Said the warrior. He went from calm and strong, standing with perfect posture, to a lunging pose, his massive spear brandished, yet equally still, in a quarter second. "I also plan on not shedding blood, but I can have my mind changed on that last part at least." During that brief movement Ginro was quite sure he glimpses abs as powerful and Magma's, at the bare minimum. He was certifiably scared shitless.

"No need for that Tsukasa." The sorcerer said. "We aren't in a rush. We want their trust, not fear." He thought for a bit. "What's something you two want, I'd love to be helpful." The Tsukasa fellow backed down, standing up agonizingly slowly.

"People who follow the rules, like those that say you ought to leave." Kinro said blankly.

"A second set of guards for the second guard shift! I hate that this is a full-time job!" Ginro said, throwing out the sort of thing he was pretty sure sorcery wouldn't be able to illusion together.

"I don't know any political scientists, mentalists, or gaslighters who could make this place a successful dictatorship of the law, so I'll have to focus on the later." The weird sorcerer said. "I'm sure your rules say outsiders can't be guards? Tsukasa and Taiju are strong enough they'd make great guards."

"Guards must be trustworthy. That's a rule." Kinro said as grey as ever.

"Perfectly logical. I'm Senku by the way." Senku said, grinning. "How about a security system? This bridge has no need to be permanent! It's ten billion times too much of a weakness to have a one-use drawbridge if you were really under attack!"

"Don't touch the bridge. That's also a rule." Kinro said, yet again emotionless. "Hello Chrome. Be warned about spending so much time outside of the village, there's these strangers around."

The girl and brawny one "Taiju" turned to see Chrome walking up from the path to the bank. "Whoaa!! Who're these guys? Do they know about sorcery?"

"I'm Senku. I don't know of any real sorcery that can't be explained by science, nice to meet you!" He said, smiling. Ginro was shocked to learn the sorcerer... wasn't. Maybe he was a liar.

"I'm Chrome! I'm a great sorcerer! I can teach you all about it later!" Chrome spoke every word with a flourish.

"Sorcerer? Hm." Tsukasa scoffed. "If you are a healer though, that would be of great help, regardless of what you're called."

"He knows where to find drugs!" Ginro chirped, suddenly biting his tongue glancing to his brother.

"He does. And doesn't appear to follow all the rules about only using them when it's necessary and permission is given." Kinro said, reminding Ginro how he's a cool guy under the rules, so long as there's no rules or easy to make up ones he's fine with stuff. He didn't even try to call Ginro out for getting high sometimes.

"That will be invaluable, do you know any cool rocks or stones Chrome?" Senku said, quivering.

"Lots! More than anyone I'm sure!" Chrome bragged. "I'm the greatest sorcerer in the village, I gotta know where to find all sorts of stuff! Won't tell you what though, it's mostly trade secrets."

"This is exhilarating..." Senku cackled "-wait!" Senku pulled out a stone or carved object, like a bar or a knapstone and fumbled with and, wettinged it, and scrubbied for a second. "Is this sorcery?" He blew into his hand, making dozens of spherical clear objects, like water, only shinier like the crystals Chrome hauled around.

"YEP- Yep that's sorcery!" Ginro yelped, jumping back. Kinro stood his ground, but stabbed at the spheres and dodged them when the wind blew them close.

Chrome scoffed. "Only the most basic sorcery, I can do much much more."

Senku grinned yet again. "Where I'm from we call sorcerers scientists, because all the tricks they do make sense on a deep level, and the have the knowledge of it. Sci means know after all."

"Every sorcerery trick is cause and effect- of course! Don't see why you'd style the whole thing after it though." Chrome said, readjusting his clothes back to a comfortable fit. "Why don't I take you to my sorcery hut!"

"I'd love that!" Senku said.

Yuzuriha and Taiju stayed behind, setting up camp at the edge of the clearing. Tsukasa took down a tree with his spear, dragged it over to the camp the two were building, split it, stripped off the excess branches, and called it two benches and a bunch of firewood. Ginro was yet again scared of this beast of a man.

Chapter Text

Chrome was slightly scared of Senku's cackling immediately after he'd shocked Chrome by knowing all of his tricks. "NOT ONLY DO WE HAVE A RELIABLE SOURCE OF MINERALS, BUT WE'VE GOT PROOF THAT SCIENCE IS INEVITABLE!!" Senku continued cackling as Chrome stared at him.

"Senku, quit cackling! You haven't shown me any sorcery, prove you know any at all!" Chrome yelled, dragging Senku away from the shed.

"Well what am I supposed to do without any cool chemicals?" Senku wined.

"HAH! Told you I was the better sorcerer, you probably just watched me do the tricks really closely and made up cool names for the sorcery ingredients! You probably can't even do multiplication!" Chrome smugly crossed his arms looking down at Senku. Senku's grin returned with a passion.

"If I beat you in a battle of arithmetic can I have the shed?" Senku said, trying his hardest not to look demonically excited.

"Hmm, if you loose you and the big strong non-scary one, Taiju I think, become my servents!"

"Okay!" Senku chirped excited again, ignoring how this was probably a breach in consent to put your friend's freedom on the line without consulting him.

Senku won. And cackled again. Quite a bit.

"The scary one caught a whole deer! With his bare hands!" Ginro said, salivating. "Can I go get some Kinro? Pleaaasssee??"

"No. Rules are rules." Kinro said. He was also hungry but could wait.

"ARE YOU TWO HUNGRY!" Taiju hollered from not really that far away.

YESS!" Said Ginro.

"No. We can't accept any sort of food." Said Kinro.

"Okay I'll bring you guys some food!" Taiju rushed over and gave them some roast deer. Kinro forbade Ginro from eating it, and after much protesting from the later Kinro said if they could watch the girl  eat some of the cut they'd be eating then wait a minute to prove it wasn't poison they could eat. Ginro tore into it but Kinro ate little and slowly.

Senku walked back into the clearing, and was followed by Chrome, who looked much more subdued. "Alright! We have a technological goal!" Senku cackled. "This is exhilarating! We'll be leaping from the stone age to early world war two!"

" Tsukasa said as Yuzuriha walked away and thanked he and Chrome. He then turned to Senku much less lightheartedly (Was he ever really lighthearted?) "What is the military application and/or weaponizibility of whatever you're inventing?"

"It's among the most useful inventions of the second world war- most people would tell you, but actually they originated before the war. They were really really useful in war though, still used almost every day." Senku said, thinking about the actual tactical advantage. "Honestly in a battle they don't do too much. It's in a war where they really shine."

"Stop being vague." Tsukasa said, quite confused about what this could be, anything from a radio to a medical advancement of some kind, psychoactive intelligence chemicals, ciphers or scorched earth warfare. Or nuclear weapons. Tsukasa was almost certain there were no uranium mines in their local area, and that they'd need great explosives and high-grade steel first, but you could never be sure.

"It's a drug like no other, one could argue you're spitting in the face of death bu using it, the cure-all: antibiotics!" Senku exclaimed.

"A cure-all? CURE... ALL? YOU TOLD ME CIVILIZATION THREE THOUSAND YEARS AGO WAS ADVANCED, NOT ABLE TO CURE ABSOLUTELY ANYTHING!" Chrome cackled with a Senku-like mania. "THAT'S COOL AND ALSO CRAZY!"

"I approve this plan, I was worried for a second. Is anyone specifically sick? This doesn't seem like a spur of the moment thing." Tsukasa asked.

"Uh, well, Ruri is." Chrome said, much less enthusiastically. "But I said I'd find a cure! And I found someone who knows about one! And I'll make him make me do most of the work so it really counts that I found her a cure!"

"Senku, you don't do favors out of the goodness of your heart. Whats in it for you?" Tsukasa said with a quite unappreciative stare.

"Oh nothinggg..." Senku said in a sing-song falsetto. "I just wanted to help, and progress technology, I mean Chrome-kun's a friend! And friendship is magic! I want to be friends with more people, and helping Ruri-chan might help me become friends with her friends, and her, and the chieftain and priestess, cause those would respectively be her father and her, so those might be friends I'd make!"

"Political power, got it." Tsukasa nodded. "How do we make these? And will there be enough for anyone else?"

"We don't want to overuse the drug, dangerous and all with antibiotic resistance, and there'll be a limited supply, but with only a village and us even an small epidemic could be handled with preparation." Senku said, then grabbed and stick and walked to a grass-less area of the clearing. "There's two ways to make the ultimate cure-all! Organic processes, in other words we find some special living things and exploit them, and the other option is... rocks!"

"How would you make drugs out of living things? Like a plant? Or a bug! Are there magic science bugs that drinking their blood gives you their life force!?" Chrome gasped and Taiju started looking for bugs.

"I know about penicillin, but I've never heard of making antibiotics with rocks! How's that work?" Yuzuriha said, working on a project of some kind.

"I know that penicillin isn't the only antibiotic but I'm blanking on all of them aside from amoxicillin, and I'm pretty sure that's also from a microbe." Tsukasa said, hand on his chin thinking.

"Amox is just another variant of living things, in fact most antibiotics are. I'm talking about Sulfa drugs! More properly Sulfonamides, they're made from rocks and stuff. Pretty decent but for a pre-stone world civilization they're just not as good as penicillin and other organic antibiotics." Senku drew a rock with a face named Sulfa and a funny amoeba with a face named Peni.

"So what's better?" Chrome asked. "Sulfa drugs seem cool cause we already have lots of rocks but I also own and know about tons of plants and animals so will the benefits of this Penicillin make it worth it? Also what's a microbe?"

"Microbes are living organisms too small to see, some of the biggest are identifiable as tiny specs of dust but those are only sorta microbes. In other words you don't know the this area as well as you think. We'd need to attract the right molds, and get very lucky oven on top of that. Contrast this with Sulfa, where we need known compounds like salts and metals and vinegar and alcohol. No ambiguity worrying we've got the wrong mold, no betting that we some get the magic super green mold so much better it breaks reality." Senku drew an hourglass and a d6 in the dirt next to Peni, and a set of scales next to Sulfa. "Unless one of you is hiding microscopes, ten billion sterile test locations, and some trained biochemists in this stone world somehow, we're making sulfa drugs."

"WHOAA! So it's sulfa drugs we're making then? A hard fought stone path to the cure-all!" Chrome shouted, cackling again. "I'm a master sorcerer, you're a sciencer or doer or whatever, and you're super strong!" He exclaimed, pointing to Tsukasa. "Let's get these drugs then!"

"Nahh." Senku chuckled, and started drawing something in the dirt. "We aren't gods, able to cure any disease with our skills, or even geniuses, we stand on the shoulders of giants, I didn't invent sulfa drugs or even this path to them!" And he stepped aside to revile the path to sulfa drugs he'd been drawing.

Chrome leaned over to look at the diagram. "Who did make those things?" Chrome asked, confused, and slightly miffed to not be a god.

"Gerhard Domagk discovered sulfa drugs, and this path was made by an American doctor I knew in case the world ended, his last name started with X, would've made a great comic villain, very megalomaniacal, you'd love him, Tsukasa would try to kill him." Senku stated matter-of-factly. "But that's irrelevant. The point is, science isn't like sorcerery, you don't mix two things together and call it a day. You mix two thing together, say no, do it again, repeat 10 billion times, call it a day. Tomorrow you'll figure how to remove ingredients from the mixture because that might help. You crawl around slowly, improving on things, patching up problems, and never in fields you invented. That's how we could fly and cure plagues before the green light, not because we were magically more developed, but because we spent centuries slightly improving and complicating stupid ideas until they were genius."

"Green light?" Ginro asked, again sneaking away from Kinro.

"Oh yeah, uh, thousands of years ago a green light turned everyone to stone. That's why there are statues everywhere. We're statues who came back to life, and you guys are probably just the descendants of people who did something similar." Senku said with a shrug.

"WHAT THE HECK?" Ginro screamed.

"Busy." Senku waved him away. "So this is the plan! It's got tons of steps and could take months."

"Months!?" Chrome gasped.

"WAIT I THINK YOU JUST HIT YOUR HEADS AND GOT HIT BY GREEN LEAVES OR SOMETHING I DON'T DESCEND FROM THE CREEPY STATUES!" Ginro screamed, very unnerved by how matter-of-factly Senku told him something impossible.

Tsukasa pushed Ginro back to toward guard post. "If you want to help ask me or Senku what to do, otherwise quit it and do you job."

"Yeah, quit it Ginro, we're standing guard not working with these people, we need to make sure they don't do anything to us, or try to sneak in." Kinro said, pulling his brother the rest of the way.

"Anyways, Senku, where can we find Iron, and don't you need to smelt that? Should I find a clay deposit for bricks or something?" Tsukasa asked Senku.

"Clay? That'd be great Chrome, point Tsukasa in the right direction, he's a master tracker, he'll find the rest of the way himself, I need you to find the iron!" Senku said, to which Chrome pointed towards a stream and noted that a lot of the riverbed was just silt, and to head downstream if the search seemed futile.

"Thank you Chrome, I'll be back when I've found enough I need Taiju's help, unless you need him to transport Iron, still don't know how you'll find that without mining equipment." Tsukasa said, and then before leaving he stopped himself. "Senku, I'm going to gather the nitric acid from the cave tomorrow, will that effect your schedule?"

"Nope! Go ahead, just please don't go make an evil empire, if you so please." Senku said, then turned to Chrome. "I bet you're wondering what iron is, aren't you?"

"Tsukasa said you smelt it so I'd guess it's a metal-containing rock, when we were in my cabin you mentioned we could smelt my cinnabar to get the metal. But how'll it help us make the antibiotics? What's a metal anyways? And what's smelting?" Chrome said, thinking.

"Dam you're very perceptive. Close, iron is the metal itself, you don't smelt metals, you smelt ores. Cinnabar is an ore, and iron has a few ores. A metal is a special material where everyone shares electrons like good friends. Smelting is cooking a material until it breaks and the bits that like to share can find each other instead of being stuck with bad friends."

"That makes very little sense. Do we need equalized Elecros in the antibiotics or something?" Chrome said and thought about what the ores might look like.

"Nope! Electrons barely matter in the reactions we'll be doing, their default behavior will suffice." Senku said, and grabbed Chrome's shoulder. "But we still need the ores, and you should know where they are!"

"Well what do they look like?" Chrome asked, and leaned back from Senku's grasp.

"Black, usually, with a red coating. Black sand is basically the best we could ask for, it's also not unusual in Japan. Almost always slightly heavier than other rocks." Senku hummed in thought. "Black crystals, often triangular, and big red stripy rocks are also really good."

Chrome thought for a second then gasped. "DOES IRON ALWAYS POINT NORTH!?"

"Well, no it- wait, no I can do that if you magnetize it." Senku said as his eye's widened.

"MWAHAHAHA I, THE GREATEST SORCERER OF ISHIGAMI VILLAGE ALREADY HAVE IRON! I'LL BE RIGHT BACK!" Chrome rushed off to his hut.

"What. The. FUCK??" Senku screeched, staring into the void blankly.

Yuzuriha gasped before asking Ginro. "IS YOUR VILLAGE ACTUALLY CALLED ISHIGAMI VILLAGE?"

 "Yes?" Ginro said hiding behind his brother, and then he felt a breeze, looked up, and saw Kohaku standing on the bridge's post.

"What's going on here?!" She asked, glaring at everyone and noting that Tsukasa wasn't present. "You're being awfully loud."

"WHAT'S THIS VILLAGE'S NAMESAKE?!" Senku said, or screamed. Either was it was barely intelligible.

"I'd have to ask Ruri-nee. I see you didn't listen to me and stay away from my village." Kohaku said, and jumped down from the post to stand in front of Ginro, giving him something new to hide behind. "And I also don't see your em em ay fighter."

"Well then who was your founder?" Senku asked, calming down.

"Same answer as before. Anyways what are you doing?" She said.

"We're making a cure for Ruri's sickness!" Chrome burst out, though Kohaku didn't seem to take the idea seriously. "Why were you guy's so weirded out by the villages name?"

"That's something I'm going to have to meet Ruri about." Senku said. "She sounds like quite a person, could you three" referring to Ginro, Kinro, and Kohaku. "possibly let me into the village?"

"No." Kohaku and Kinro said.

"Well darn it. Would you help us with the iron Chrome's helping us find- oh wait you're back! You said you have iron already, didn't you?"  Senku said, looking at the newly returned Chrome, who was holding a bowl.

"I DO HAVE IRON!!" Chrome cackled. "It's called the north pointy stone! Kohaku you know about this sorcery, explain it to them."

"It's very useful for sorcery." Kohaku said, and took it from Chrome and began to slowly turn it, and allowed everyone to see the leaf floating on the water that was in it. The leaf had something on it and didn't turn with the bowl. "This stone, the thing on the leaf, tries to point to the north, and without rubbing against something to slow it down, for example if it's floating on water or hanging from a string, it can point itself that way." She picked the leaf and stone out of the bowl, spun them around, and put them back it. Magically they turned around.

"WHOAA!" Ginro said, starring.

"So you guys have magnet! That's great!" Senku said, and stole it.

"Wait you know about these- also give it back!" Chrome yelped.

"Nahh, we can use it to find iron! You said the riverbed that way was mostly silt? That'll mean it's full of iron!" Senku said.

Everyone began to walk off, except Kinro and Kohaku. "Go on Ginro I'll keep your post, go hang out with the sorcerers." Kohaku said, much to Kinro's disapproval.

Chapter Text

Tsukasa walked back towards the clearing with about 50 or 60 kilos (hundred and some pounds) of good looking clay on his shoulders, held together by a woven plant fiber net and leaves. The sun had just recently set, but he was sure Senku had enough planned they'd take a bit at least before sleep was an option. He was walking upriver, and right before turning away from it to the clearing he heard laughing, and peaked through some branches to see all the others (including Ginro, surprisingly) in the river, seemingly just kidding around. There were only two people working, a kid with a watermelon on their head, and Taiju. They seemed to be getting something from the riverbed. Perhaps panning for iron? Tsukasa was quite sure that wasn't a thing. He sighed, and walked the rest of the way to the clearing, where Kohaku had taken Ginro's place as a second guard. He threw some large leaves on the ground to prevent dirt from sticking to the clay, and then threw the whole pile of clay onto the ground, shaking the rocks around it. His shoulder hurt like it'd been hit by a log.

"Dam. You're strong. And quite stupid, what use does that much clay even have?" Kohaku said, scoffing.

"Clay is a good thermal insulator." Tsukasa said. "Great even. You can use it to hold in the heat of a fire. We'll have to smelt or at least melt whatever iron they're gathering over there."

"Weird science sorcerers do strange things with fire all the time." Kinro said.

"You can say something other that "rules are rules" then." Tsukasa said. "Are you nearsighted?"

"What?" Kinro said, and Kohaku looked confused, and slightly mad.

"It's not an insult, I just want to know if you have vision issues." Tsukasa said, stretching his shoulder.

"I- I have the fuzzy sickness." Kinro looked down ashamed.

"I never would have guessed!" Kohaku exclaimed, shocked. "You're such a strong fighter! Well don't go telling anyone Tsukasa, they'd think less of him. They shouldn't but well..."

"As much as I value the healthy young generation, I don't think discrimination based on genetic conditions can be tolerated." Tsukasa said. "If anyone discriminates on anything as petty as that I'll stop them. And I'll get Senku to make some glasses for you, I'm sure he knows how, and glass can't be that difficult to make, it's just some specific sands I think."

"Two questions." Kinro said, confused. "What are glasses?"

"Clear things you can look through that'll fix your vision." Tsukasa said, and began breaking apart branches to make a fire.

"Hm. Sorcerers always pretend to be able to fix stuff like the fuzzy sickness." Kinro said.

"Your second question?" Tsukasa said.

"How could you tell? You don't seem like a spy who'd listen in on me, or a sorcerous type who'd steal secrets." Kinro asked.

"Well you just squint at stuff that's far away a lot." Tsukasa said with a shrug. "And your brother points stuff out for you more than you do for him by a rather large margin. I'm a professional fighter, I have to be able to be this observant."

"I suppose." Kinro said, thinking. "But the most perceptive person I know is Kohaku, and she didn't guess at all."

"She'd have always seen you squinting at stuff, and always known you as one of the stronger fighters, she wouldn't think about it." Tsukasa said, and started the fire. "You guys want to sit down? It's getting cold."

Kohaku sat down. "You're right, I always just assumed his eyes were more squinty than mine or his brothers. My sister talks about 'preconceptions' sometimes, I think it's one of those."

"Your sister sounds very smart, I'd love to meet her." Tsukasa said, and began slicing the uneaten venison up. "Hey, Kinro, could you make a sort of three-branch tent shape over the fire, I'm going to smoke this meat for later."

Kinro sighed and finally left his post. "I've never smoked meat before, I've eaten smoked meat but I have no clue why it last longer. I suppose your science knows why."

"I think it just makes the meat inhospitable." Tsukasa said. "You two heard about microbes right? They also make your food go bad. Eat the good parts and excrete some useless or poisonous stuff. Also eating microbes is always dangerous. I heard that smoke is full of equally poisonous particles, but they don't really hurt us that much, and absolutely does ruin any microbe's days. Also the heat removes all the water, and microbes need to drink same as people."

"Science is weird." Kohaku said shaking her head. "I wonder why people turn to it or sorcery. What could you need to do that needs such strange ideas? It's probably all wishful thinking and silly colored fires."

"Ruri's your sister right?" Tsukasa asked Kohaku.

"Yes." She responded.

"Then saving her. For two million years people had sisters and brothers and lovers they'd kill to save. I have nothing against that. I mostly dislike the people who saw medicine and defenses and used them for war. Or the monsters who hold cures for ransom." Tsukasa said, and grinned. "But I'll never let that happen again."

"I suppose if it's not a scam. Just don't really believe in Senku and Chrome." Kohaku said, before glancing into the foliage. "Also they're coming back."

"You are perceptive, it's too dark for me to have noticed them." Tsukasa said, nodding to Kohaku, and then began hanging the hide over the structure Kinro had built, and hanging the meat in it.

"Hey guys!" Senku said, pushing through the foliage. "We got some iron sand and a friend!"

"Hi!" Suika said, reveling herself.

"Suika! You went with them to find this iron stuff?" Kohaku said, patting her on the head and leading her to the fire.

"You know her?" Tsukasa asked, wondering how this terrifying worrier met this watermelon-wearing kid.

"Yeah, Suika's a hardworking cutie." Kohaku said with a grin, causing Suika to blush.

Senku's mouth twitched and he made a small "mm" sound. Tsukasa made a sideways glance at Kohaku's expression, and then checked to see Suika's reaction to the complement, noting the color change in the small part of her cheeks that were visible. The callous parts of them had noted an exploitable emotional bond.

"Hey guys, I'm tired, I'm gonna head to the sorcery shack and get some sleep." Chrome said, dragging in a semi-lucid Ginro.

"Kinroo- I'm tired, when sleep?" Ginro slurred.

"Are you drunk or something?" Kinro said and rolled his eyes. "Or are you just so lazy you'd get this tired just from splashing around?"

"Lazy." Ginro clarified. Kinro grabbed his hand and said he was taking him back into the village to get some sleep.

"Bye Ginro" Suika said with a giggle. "Suika was helpful!"

"You need sleep too Suika. Why don't you go into the village now?" Kohaku said, ushering Suika to follow the brothers over the bridge.

"Very hardworking kid. Gave Taiju a run for his money at iron sand gathering." Senku said with a smirk. "Honestly outdid him, but you might notice he hasn't come back yet."

"Yeah, where is he?" Tsukasa asked, smothering the fire to make it smoke more and burn less before closing off the meat for the night.

"Still out there, said he'd come back when no more iron dust would fit in the basket." Senku chuckled. "That's why he's a better iron gatherer than Suika. I had her do it when she had the energy but Taiju will always have energy."

"You seem a little too eager to use people." Tsukasa said, looking down.

"I saw you when Kohaku and Suika were interacting. You were ten billion percent measuring how much they'd do if they thought the other was at stake." Senku said, with a completely straight face.

"You didn't address my point, or respond negatively to the idea." Tsukasa said, with a much straighter face. "And I don't think I'd act on anything like that. I'm just observant."

"Who're you resurrecting tomorrow?" Senku said with a small grin creeping onto his face.

"I was thinking about someone who'd know about other people to resurrect. And if possible- a friend of mine." Tsukasa said, his voice wavering on the last part.

"Liar- that's totally wrong. You, first off, definitely don't have friends, and secondly, had some sort of much better idea in the works you decided to scrap since it was purely based on what they could do for you!" Senku blurted, his grin wider now.

"I hate you. You're supposed to be a genius but when it comes to emotions you fall on your face unless it inconveniences me." Tsukasa said, rolling his eyes and groaning.

"Well who were you thinking of? I'm sure it was a good idea and I like good ideas." Senku said, humming a little.

"I knew this guy, more antiquated then knew, but either way he was incredibly good at talking, very smart too, charismatic? He called himself a mentalist. Would be very effective at getting us an audience with this priestess." Tsukasa said with a sigh.

"Great plan!" Senku said. "If there's one thing out party is currently lacking, it's social skills, so I can't wait to meet this guy!"

"Party? Oh like an RPG." Tsukasa said, before rubbing his shoulder. "I'm gonna go stretch, maybe run few miles, then sleep."

"Cool! I'm gonna go sleep with Chrome, uh slash nsx, he's cute but I'm very ace." Senku said, rubbing the back of his neck with a soft giggle.

At one in the morning Taiju yawned, and decided to clock in now that the basket spilled every time he moved it. He extended the rim with some leaves to prevent spilling, but this couldn't hold the weight of iron, so he didn't get any more. It was many, many kilos of iron, and he struggled to lift the whole thing. He hauled it up the bank and into the forest. It was far too late for there to be much light but he felt safe. The moon was nearly full so he could see any movement and make out large obstacles, and he was quite sure Kohaku and the rest of her village wouldn't tolerate lions in their area. He was, however, very alertly listening. This allowed him to hear a repeated clacking. There was no regularity to it, but it was fast, and all from the same direction. Taiju took a small detour that way and saw Kohaku and Tsukasa fighting at breakneck speeds with bamboo sticks.

Kohaku had two sticks, which were shorter. Tsukasa had a large, flexible rod, which he wielded like a bō staff. He was concentrating much more on defense than offense. Every time Kohaku stabbed at him he smacked her stick out of the way, then continued the motion, which would whack her with his staff from the opposite angle she attacked him from. However she always dodged, or blocked. When she blocked, he kicked her in the chest. When she dodged he targeted legs or head while she was moving. She'd inevitably block or doge this strike as well, but this had the same effect. Either way, she was forced to back up. Even when she tried to get in a counterattack, Tsukasa's leverage over his staff was incredible, and would inevitably mean his bamboo stick would intercept one of hers. Over time she got better at exploiting the flexibility of her opponents weapon, as it'd take a second to spring into place or reverse direction. Whenever one of Tsukasa's attacks was uncharacteristically not devastating she'd stab right where the staff has just been, centimeters behind it. The first time she did this she bruised his thigh, though he managed to turn it around through shear force, making the stick creak, and smack her hand so hard she was quite sure it'd turn all weird colors whenever the color vision turned on again. No matter how good her eyes were her cones would never be able to see color.

It was about her third fully going-for-it stab when she spotted Taiju in the foliage. Tsukasa had picked up on the tactic by now and would shift out of the way, but this time he barely made it. Kohaku noticing Taiju was probably the only thing that had prevented him from being, well mildly hurt to be honest. The slow dodge, however, was not an accident. "Taiju's her-"

Tsukasa's staff seemingly blinked from one location to another, the former being at the end of a swing, the latter being Kohaku's side. It whacked Kohaku across the clearing, and Tsukasa nodded to Taiju, having now noticed him. "Well we'd better give Taiju a show. I'll try out some purely offensive moves." Tsukasa switched his grip from somewhere around a meter between each hand and the end of the staff, to both on one half, one next to the end. This was closer to a quarterstaff, or, not coincidentally, a sword.

Hi! I'm Mecha Senku! I'm here to explain the difference between bō staffs and quarterstaves! You humans are amazing at whacking stuff when you happen to be levers with a long distance between the force and load, or are made into levers like that by our tools. Quarterstaves sure as hell make long levers when combined with two arms, and one can very easily shatter someone's skull with one. There's a reason bat'leths are wildly impracticable, and that's cause while bat'leths are the sorta levers where the distance between the action point and load is tiny. However they're great for defending, because due to some Newtonian stuff, it's hard to turn stuff around without it being a lever, but good attacking levers also work backwards, so when partying and blocking you need to resist the modified force, not whatever the person striking you just did. There's also another benefit of having an ineffectual lever, bat'leths can block from both directions, and turn around really quickly. This is why you grip a bō staff at equidistant points on the rod and grip a quarterstaff at either end of one quarter, as the bō staff is meant for martial arts training and quick block-counter combos, and a quarterstaff is built to kill people and outreach other cheap weapons, at the cost of it's only defense being "crush their skulls or at least shins before they stab you or steal you staff."

You can prove the physics of this with two sticks and a friend, if you've got one. Take a stick and hold it like a sword. Have your friend hold theirs like a sword and whack yours. Note how hard it is to keep yours stable if they put elbow grease into their attack. Hold your stick like a bat'leth and have them hit both in between your hands, and past them. Note how much easier it is to stabilize everything. Repeat with the attacker holding their stick like a bat'leth. Note how pathetic their attacks seem. This is definitely safe and not going to get someone injured.

 

Tsukasa charged Kohaku and began to pull on the end of the staff with all his might and push into the other gripping point with an equally insane amount of force. Acting as a weaponized lever, the staff accelerated extremely quickly, and cracked like a whip, hurting Kohaku's ears as she barely dodged, leaping to her feet to counter attack. The momentum from the swing was too strong for Tsukasa to block, so he just kept charging and finished his swing, not hitting her with it, but shoulder-checking her. She still whacked him, being confident in her ability to get out of the way, but as she stepped back, he pivoted his staff around, exploiting it's lever-hood, and swept her feet out from under her. He grabbed her shirt and chucked her underhand across the clearing. She skipped like a stone and rolled to avoid another charging whiplike swipe at her head. This time she stood farther back, avoiding the quick turnaround sweep. He quickly turned it around again, swiping at her face, slowing it's momentum, rolling it to preserve some of the momentum, and swiping again. Faster and faster he did this over and over until Kohaku understood the pattern and followed the staff after a swing.

Tsukasa had three choices. First, he could do what he'd been doing, slow down, whip around, and smack with terrifying force. Second, he could keep going, not slow down, but speed up, whipping it around his head and having an unstoppable strike in the works for when it got back, sure to knock her senseless. Finally, he could shift his grip, and do a bō staff-like counter, and give up a precious bit of momentum his combat had. He decelerated the staff, and loosened his grip so he could use a very ineffectual block with the part of the staff he was using as a handle. The first option, what he went with, was imperfect, but if he could survive whatever she did until the staff turned around, he could force her back and retain his combat momentum. Kohaku tackled his staff right as it hit it's slowest point. She went for a kick but Tsukasa was faster. No matter how unprepared he was for that tactic he could always just kick her. He lifted her and the staff into range of his foot and used a quick front kick to her back to knock the wind and probably ribs out of her. She crumpled off the staff. Tsukasa began to shove his full effort into his staff, getting back up to speed. He spun around to whip it into her to signal the end of the fight, but then saw her moving. She surged back with what was probably the last of her energy. He swung it at her harder, now sure she'd block. She rolled out of the way and his staff shattered against a large rock. She immediately kicked him in the balls. He stumbled, painfully, forward a step. His opponent forced herself up, into the dominant position. She went to hit him on the head to knock him out when he lunged forward, gritting his teeth through the pain and punched her in the face. She passed out instantly.

"You two are insane!" Taiju said, or screamed, but for Taiju this was a lower volume scream. "I can barely even make your weapons from the tree branchy bit and you're fighting at craaazy speeds!!"

"Yeahh- Sorry it's still quite painful to move." Tsukasa said, before going to pick up his downed foe. "Let's head back. We all need sleep, and I'm sure Kohaku will want to spend a little extra time at the hot springs tomorrow soothing herself, what with all the bruises I'm sure I gave her."

"Alright!" Taiju said, and heaved the iron onto his shoulders.

"You two are banned from sparing at full power." Senku said to the piles of bruises with bodies incidentally attached that claimed to be Tsukasa and Kohaku. "I need all the strong muscle people I can have, and you two are acting like you can be sleep deprived and in pain when I need your help!"

Chapter Text

Kohaku walked across the bridge covered in bandages. "My family thinks I'm crazy or something, seriously, it was just a cool training fight." She sighed.

"So you've been banned from doing this again by another authority?" Kinro said rolling his eyes.

"Yeah, but still! I'm fine!" Kohaku said, waving a braced hand around in exasperation before Senku appeared out of nowhere and put his hand on her shoulder.

"Kohaku, you're going with Tsukasa right?" Senku asked, with a piece of bark attached to a pace of charcoal by a string as a clipboard in his other hand, which was covered in manic scrawling.

"Sure, we'll both be passing the springs, right?" She said with the biggest shrug she could manage without straining her very damaged ribs.

"Yeah, okay, he's leaving in like two minutes, so get ready!" Senku said before rushing over to Suika, who was helping Tsukasa pack his smoked meat for the trip. "Suika! I need your help!"

"Suika loves being helpful! What do you need?" Suika said with a grin.

"Go to the river and fill this basket with iron dust." Senku said, shoving a small basket into her arms. "We should have enough but it'll take us long enough with the bloomery we might as well add a little more."

"Suika's got this!" She exclaimed and pulled herself into her watermelon to rush off faster.

"TAIJU! Go get me more clay!" Senku yelled mostly at a tree. Nevertheless Taiju bolted into action and ran to go get more. "Chrome! We're making a bloomery! Bring me your charcoal!"

"What's charcoal?" Chrome asked, puzzled.

"Burnable black stuff, like my pencil," He lifted his "pencil." "that you get from burning wood. Get all of it you've got!" Senku said, making more notes on his "clipboard."

"A bloomery is a hollow tower of dried clay filled with a four to one mix of charcoal and iron ore, in this case sand. The heat from the burning coal heats the iron up to the point that the oxygen incorporated into the sand can't hold onto anything else and it gets mixed into the carbon monoxide that's in the smoke, latching on and making it CO2, which is both removing the gunk from our iron and making the smoke less toxic!" Senku said to his array of listeners, Suika, Taiju, Chrome, Yuzuriha, Kinro and, Ginro.

"So, we cook the ore in a tower and get iron? Sound's easy! What do we do with the iron we get?" Chrome said with a chuckle.

"Not really, you see charcoal burns at about 700 degrees, and iron, well, the oxygen hugs on super tight. It takes 1500 degrees to get it to let go." Senku said, shrugging.

"So should we get better burnable stuff or what? If i change the fire's color will it burn hotter?" Chrome asked, thinking of other things you could do it make a fire hotter.

"Nahh, none of that stuff, we just gotta blow on it!" Senku said with a grin.

"That only makes like little firestarting bits of kindling burn better, and if you do it too much it'll blow out the fire! How can we get it to go up by..." Chrome started flipping his fingers up and down around like he was counting. "7- no, 800 of these 'degrees', just by blowing on it?"

"Well big fires don't go out without like full on explosions, so blowing will never hurt it, and well just blow on it a lot!" Senku exclaimed. "It actually does effect all fires, put usually there's enough air anyways."

They'd failed. They simply didn't have the stamina to keep that up. After only a few minutes Taiju was the only one still working the primitive bellows. "We're- going to- *gasp* need some more, uh, manpower." Senku said, panting from the effort.

Kohaku and Tsukasa had finally reached the springs. They immediately fell into neighboring pools, and lay there for a while. "I'm going to have to keep going, this is only a rest for me." Tsukasa said after 10 or so minutes.

"You sure you can wake up the statues?" Kohaku asked.

"Yeah, seen it happen before. I'll be back to the village by the day after tomorrow with some new folks, you should be able to make it back by tomorrow, right?" Tsukasa asked in turn.

"Yeah. Good luck." She smiled.

"Suika- uh, Suika can help!" She said for the third time. Finally Senku said something other than "I know I know".

"Wait, you mean you have a specific plan on getting manpower and don't just want to be helpful?" He asked.

"Yes! Suika's great at learning how to get people to do things!" She said, finally recognized.

"Ohh I'm so sorry kiddo, I probably just ruined your opinion of me by ignoring you, but uh, what's your plan?"

"Suika can look like a regular 'Suika!'" She said, engaging stealth mode, or just hiding in her watermelon, whichever you prefer. "I hear all sorts of stuff like this! Like I know about Kinro's-"

"Suika, quiet!" Kinro said, shushing her.

"Sorry..." She mumble, before looking back to Senku. "Well, Suika can find out all sorts of other people's goal too! She can find out what we can give them for their help!"

"That's a great plan, Detective Suika, I task you with finding me what people want so we can get their labor!" Senku said, repressing a cackle.

The watermelon-clad child immediately bounced off cheerfully.

"So Garnet, Sapphire, and Ruby want boyfriends, that's a non starter, but uh, one of them wants to be spoiled. What does she want?" Senku asked Suika.

"Tasty food I think! Like fish and stuff. Speaking of fish, the biggest eaters of the village want something other than fish to eat." Suika said, grinning with pride.

"That's our Detective Suika!" Senku said with a subdued cackle. "This is a great lead, we just need to make some good food!"

"What's food got to do with sorcer- er, science?" Chrome asked, scoffing. "It's just girls heating stuff in weird ways, and sometimes throwing salt on it." Yuzuriha smacked him.

"Well why do you think salt makes stuff taste good? It's a chemical compound that is ionic, that's some fancy chemistry stuff, but you can also think of the tasty flavor of a fish glutamic acid makes it umami, this is all science! Food is science, and we can use that." Senku looked over at Suika, who was picking a plant off the ground, petting a dog. She stopped petting it and waved the plant around. The dog chased it like it was a cat instead of a dog. "Is that- Suika what kind of plant is that?"

"It's a foxtail! It's Suika's best friend, Chalk's, favorite toy!" She said with a grin, presenting her dog to the world.

"Foxtail is a grain! We can make one of the tastiest pre-stone world foods with this!" Senku said, cackling again. "Everyone loved this back then, with millions of options of what to eat, in this stone world, with little but fish, everyone will become our laborers!" Senku stopped cackling, noticing people probably thought he was as megalomaniacal as his mentor. "Kinro! You'll be the main one cutting down our foxtails, cause doing it without a blade would suck, and Tsukasa and Kohaku are gone, but flint will only work with a long blade like Kohaku's, so I'm improving yours!" He stole Kinro's lance and Chrome's cinnabar, which they both protested, but neither stopped him. He cooked the  cinnabar until mercury melted out, sprinkled in some secretly useless gold dust, and dipped the lance in the liquid. It cooled and hardened, and gave Kinro's lance a golden coating. "Here! It's edge can be restored with a whetstone, unlike flint!"

"Thank you for enabling me to do your dirty work." Kinro responded sarcastically, before doing what was asked of him and cutting down the foxtails he was asked to. Senku instructed everyone to beat the plants agaisnt rock, which caused bits and pieces of the foxtail to fall off.

"You don't expect anyone to eat this junk, do you?" Chrome asked, staring morbidly at the mix of seeds, dirt, and stems that Senku seemingly planned on making food out of.

"I most definitely do!" Senku said, delighting in Chrome's disgust. "However a good portion of this sure is junk, we'll have to get rid of it." They mixed their yield with water, and allowed the good stuff to settle, removing the chaff and stems from the top with strainers Yuzuriha made. They then removed the pebbles and dirt by straining out the seeds from the bottom, which left behind smaller, heavy particles like dirt. They washed them a little more, and lay them out to dry. Suika stole a mortar and pestle and they ground the seeds to dust with it, before finally winding up with a pile of flour. "This is foxtail flour! It'll make some wonderful dishes, but for now I need our master detective to go steal a bird egg."

"Suika and Chalk are on it!" Suika said with salute, and showed her dog a feather to track down a nest by smell.

"Aside from that all we need is potassium carbonate, found in wood ash, and some water!" Senku said, cackling. "Some fourth century mongol found out that by mixing all of this together you could make a miracle food! They were probably something like Chrome, an idiot who just liked trying stuff! Eventually they found a really good thing, just by giving everything a shot."

Chrome watched Senku chop the dough he was kneading into strips, thin them out, and throw them in a bowl with all the meat they could muster, some leafy greens, and a few fish. Chrome set up a fire and they brought the soup to a rolling boil. "This- smells amazing!" Chrome shouted, leaning over the hot soup.

"Thousands of years ago we called this scientific delicacy... RAMEN!" Senku said, cackling even more fiercely.

"YOU MADE RAMEN?! WHAT'S NEXT, CELL PHONES?" Taiju yelled, staring at the weirdly green ramen. "I CAN'T BELIEVE WE CAN MAKE THIS ALREADY!"

"I'd better taste this for poison, who knows what foxtails could do to water?" Chrome said, sounding entirely logical, while salivating. "That's the way of a sciencer, after all, trying new things, fearlessly!" He took a huge bite of ramen, and began spasming on the floor, veritably screaming "MMMMM", he recovered himself, and went to tackle the ramen bowl. "RAMEN IS- DELICIOUS! NOT POISONOUS!"

Everyone dug in and absolutely loved it, aside from Yuzuriha and Taiju. "What's up guys?" Senku said.

"It's, uh, bitter. Weird aftertaste." Yuzuriha admitted.

"Yeah! I love the meat though, and veggies aren't bad! Just avoiding the noodles." Taiju quietly screamed.

"Yeah, suck that we don't have real wheat. I'ma go choke mine down. Think of it like medicine, it's super nutritious."

"We'll take over the village with food! MWAHAHA!" Senku cheered, as Chrome pulled their new ramen cart next to the bridge. He could hear the villagers noticing the smell as he uncovered big pots full of ramen. As all the villagers poured over the bridge to taste whatever smelled so good Senku saw Kohaku, carrying a giant jar of springwater. "Welcome back! You'd better take a bowl of ramen to your sister for me!" Senku said to her.

"Always focusing on business aren't you... what's ramen anyways?" Kohaku said.

Chapter Text

Gen's mind returned after who knew how long. His first thought was 'wrong wrong very wrong get me out out' , and then he began to think more rationally. ''Why would my mind return after this long? I had to have been lucid yet trapped at least a century, what changed since I fell asleep? I- I think i feel something.' Some terrible stinging sensation spread across Asagiri Gen's back. It was quickly followed by a cold air on bare skin. 'I'm alive again, this isn't a dream, I can escape!' He pushed through the stone, and stumbled up, finding himself naked, and covered his chest, and stayed down to cover his crotch. "What happened..."

"It's been 3,700 years since we last met." Tsukasa said, noticing Gen's defensiveness of his chest. "I'm Tsukasa Shinshio, here, have this robe."

"Thank you." Gen said, covering his breasts and tying it around his waist. He stood up in a hunched position and felt a tightness in his chest realizing the first thing he did after 3,000 years in stone was undo years of passing. "You're an MMA fighter right? Having trouble remembering anything else about you. What caused.. what... erased all of, uh, civilization..." Gen stared at the wilderness around him, miles and miles of it with no end in sight. "Is anyone left?"

"Myself, a scientist of great skill, a craftswomen, and a living steam engine have been resurrected from stone statues like you came from, or like those over there." Tsukasa said, pointing at a few statues of people Gen remembered being right outside the window when the green light came, buried up to their shoulders in the soil. "There's also a village that is most likely descendants of other resurrected folks."

"Wow, uh, that's it. That's all that's left of civilization. Why'd you save me then? What use am I when there's less than a thousand people on earth?" Gen said, holding himself together by gripping his own shoulders.

"Well first the village isn't onboard with science and makes no sense on several other counts, and we're banned from meeting the priestess who seemingly has the answers, and secondly, we're rebuilding society. All of it, well, maybe not the bad, but we're going to need people able to get everyone we resurrect behind our goals." Tsukasa said, realizing a little too late Gen might have needed emotional support.

"Okay... So let's get going then! This priestess won't talk to you on her own! Well, I don't know, but it'll sure be easier if I'm there." Gen said, standing up straight, before hunching back over again, and glancing down.

"Not yet, there's one other person I have to resurrect." Tsukasa said, and began walking towards the foliage, remembering where she was. "She's this way."

Gen stumbled and followed after. After a while Tsukasa found a half buried statue of a women. Tsukasa began making her some clothes out of hide he had on him. "Hey can I have some of the softer and stretchier hide, if you've got that?"

"Sure, here you go." Tsukasa handed him a few long strips of hide.

"This is perfect Tsukasa-chan, thank you!" Gen said, before rushing into the trees for a minute.

When he returned Asagiri Gen was standing upright and proud. He'd fashioned his rope into a sick looking collared yukata, and tied it at his waist and neck. He was the famous mentalist, and he felt much better. He saw the women, already resurrected, dressing herself with a dress Tsukasa had made. "Hello Ms., I'm Asagiri Gen! I'm sure you've heard of me, welcome to the stone world! It's been 3,700 years since you were petrified. This is Tsukasa-chan, he's the kind man who resurrected us both, and a famous MMA fighter!"

"You catch on quick." Tsukasa said, noticing how much more confidant Gen now was.

"Um, that's a lot to take in. I'm Hokutozai Minami, I'm a reporter, I know Tsukasa-san, and know of you as well! What are you two doing in this post-apocalypse full of weird statues?"

"I suppose there's more to tell both of you." Tsukasa said, and began to answer all of their questions, and direct them back towards the village.

"Ruri-nee!" Kohaku said, rushing up the steps with a large jar of springwater and a bowl of soup balanced on top. "I have good news!"

"Kohaku! What's that? Is the good news just that you got me soup?" Ruri said, standing up shakily.

"No! Well I did bring you soup, the sciencers call it ramen! Th-" Kohaku said,before being cut off by the chief.

"Kohaku! You wouldn't feed your sister something from those creepy sorcerers, would you!?" Kokuyo said, with a gruff gasp. "Who knows what they made it from? Rocks? Baby brains? Random plants like mustered or foxtail? Poison?"

"It's really genuinely safe, I had some, it's just tasty, not magic! Try some noodles!" Kohaku said, presenting the bowl to the chief.

"Never! 'Noodle' sounds like sorcerer-speak for baby brains!" Kokuyo said, crossing his arms, before smelling the soup. "That soup smells extraordinarily good, remove the noodles and it's acceptable. Throw them out."

Kohaku sighed and did as she was told. She took a sip to prove it wasn't poisoned, and gave it to her sister. Ruri slurped it down, at least a third of it, before her appetite abandoned her. "Ruri, can we talk alone?"

"No!" Their father answered for her.

"Please father! She just want's to talk!" Ruri said as loud as her poor lungs could manage.

"No. You can't be left alone." He said, exasperated.

"Well then I'll tell my sister the most I can with you around, and then I'll leave." Kohaku said, glaring at her father with a fire that could probably scare of a real gorilla. "The sorcer- sciencers, uh, they want to talk to you about the Hundred Tales, and the origin of the village and it's name." Kohaku said, ignoring her father.

"It's name..." Ruri said, deep in thought. "May I ask the scientist asking these question's name?"

'Scientist... only the sciencers call themselves that' Kohaku thought, before responding. "Senku does most of the asking."

Ruri's face turned pale, and she gasped, before doubling over and coughing. "Tell him- " she groaned and held her side. "To find his father's grave."

"Don't let sorcerers anywhere near our people's graves!" Kokuyo shouted, furious at his daughters. "Best if you don't tell him that at all."

The people who ate ramen enthusiastically worked the improved bellows in exchange for the soup, and soon the iron was poured into a mold, and Senku presented his iron rod with a manic glee.

"WHOAA!" Chrome and Taiju yelled at once.

"What's it for?" Ginro asked, tapping it.

"It's for making a generator!" Senku said, and ran to Chrome's hut to search for something. "We need copper to make it an electromagnet!"

"Senku! I talked to Ruri!" Kohaku ran over the bridge and pushed Kinro aside to see Senku.

"You did?" Senku said, eyes wide. "What did you tell her? Did she want to tell us anything?"

"Well, I couldn't tell her much, my stupid father wouldn't leave, but I told her your name and said you need to find your father's grave." Kohaku said, and picked up the iron rod. "Whoa this is heavy! I don't see how you'd even do that, I don't even think the founder's grave could last 3,00 years. Is this the iron?"

"That's... very interesting. I'll have to think about this." Senku said, holding a basket of copper ore and scratching his head.

Chapter Text

Gen stumbled forward again, for what was probably the three thousandth time this hour alone. A normal sane person would have called this walking, but Gen was no longer sane after a whole day of it. It was like when you say "cookie" over and over and start wondering how the word ever had  meaning because it just sounds like nothing.

"Gen." Tsukasa's said, poking his shoulder. "We're here, just thought you might want to introduce yourself on your terms."

"Thank god, my soles feel like they've been split apart." Gen said, checking back into reality, and looking past the foliage to see a hut with a small crowd around it, admiring something held by a highschooler wearing some sort of a cross between a rope and a lab coat. "Where's Minami?"

"She's heading to the village to get situated, I was headed to meet up with Senku and you were just following me." Tsukasa said, realizing just how checked out the mentalist had been.

"Oh, well, I'll make the best of this then!" Gen said, wiping his brow and pressing through the foliage. "Hello!" He said, timing it so that he'd be just the right distance from everyone when he said it. "I'm Asagiri Gen, I'm a famous mentalist, I'm sure some of you know of me, what's that object, oh- It's a mental bar... How'd you make that in this stone world?"

"Hello Gen! I'm Senku! I do know of you, mainly your silly books, but yeah, this is a iron rod. I'd love to use it to generate some electricity but it's not really ready, if there were, say, a thunderstorm, we could magnetize it and make a reliable generator, but without anything like that we might need to make some batteries to power stuff, or even make a self-exciting generator, which would need a smaller source to get it going anyways, and would overall be less reliable." Senku said, waving to Tsukasa and the new revive. "Actually, we'll have to manually magnetize this. Chrome, get the compass- the thing that always points north."

"Hmm, seems like an interesting science project." Gen said, wondering what these maniacs were planning. "I'm going to go find the village you people are from."

"Senku." Tsukasa said, waiting for everyone to step back aside from Senku and Kohaku. "How easy would it be to make glass?"

"That's probably the next thing we'll do to be honest, why do you ask?" Senku said, wondering is Tsukasa was actually thinking ahead and seeing how many requirements would just react with their storage medium.

"Good, it's just that Kinro's nearsighted and I'd like to train with him but he doesn't use his spear like a spear, given how hard it must be to make out." Tsukasa said.

Tsukasa hadn't, but at least he'd been gathering information. "Huh." Senku said, and ran into Chrome's hut. He returned with a clear crystal. "This is quartz. It can be polished into an optical lens. Usually glass or plastic is preferred for normal eyeglasses due to it's crystalline properties and stuff making it weird, but it's still used in plenty of industrial purposes." Senku melted some more copper and poured it into a long, thin mold. He waited for the wire to cool, and bent it until it resembled a glasses frame. "Honestly, let's just make glass..."

"Okay? What do you need?" Tsukasa asked, taken aback by the jump from quartz to just making glass.

"Seaweed and shells, so go diving I guess." Senku said, and then Chrome returned, and Kohaku and Tsukasa went to leave. "Wait a sec guys, there's another ingredient. Chrome! Where'd you find this?" Senku said, holding out the quartz.

"Why- I was just a little bratty kid when I found that! It's really useless so I never searched for more. It was that way." Chrome pointed, then piped up again. "By the sea, rocks come to the surface where there'd otherwise be dirt on top of them. Pretty sandy."

"Thanks- that's called an outcropping by the way. Tsukasa and Kohaku, get as much of the sand from that area as you can!" Senku said, pushing them off to get materials. He the snatched at the magnet, which Chrome pulled back before offering it and rolling his eyes at the brazenness. "Hand me that magnet! And that hammer, and that chisel!" Senku said, somewhat maliciously.

"Don't break my magnet!" Chrome said, hiding it in his sleeve, his distrust back.

"Nahh, I won't do that." Senku said. "I'll just break a chunk off of our iron!" He split off a fragment about the same size as the magnet and began rubbing it with the magnet.

"What are you doing?" Chrome said, squinting at Senku's strange behavior.

"I'm making a magnet! You know how magnets pull on iron? It got the sand with iron in it separated from normal silt right!" Senku said, noticing the two objects were just barely starting to stick together. "The finished metal is still  made of small bits, and the tugging can point them in the same way! If most of them point their tiny magnetic fields one way they add up and make a bigger magnetic field!" The magnet was starting to sort of spring off the iron, like it was being held in place until it snapped off.

"Huh? You're saying all iron is tiny magnets?" Chrome said, trying it reason how solid objects could be little objects at the same time.

"Yeah! Any given atom is a tiny magnet- er, electric field! Everything is made of atoms and so everything is! Not just iron, iron just has a helpful structure." Senku said with a shrug like this should be common sense.

"Two questions:" Chrome said, holding up two fingers. "Why doesn't my magnet just lift up everything then? If iron isn't aligned until it becomes a magnet, but can still be lifted up, why doesn't that work on anything? Secondly, WHAT'S AN ATOM?" Chrome exclaimed.

"Well, the answer's are intertwined, so I'll answer the second first. An atom is the smallest divisible unit of a material. You can go smaller, but the things that make atoms aren't matter. If you're wondering what matter is it's everything you've ever interacted with aside from light, which is a particle wave hybrid, and non-real stuff like dreams, which is an emergent property." Senku said, now satisfied with the strength of his magnets, fiddling with yet more copper. Then he started talking again. "In most things the atoms are sort of chaotically mixed. Here, look at these two magnets. These two sides stick together, these two can barely be made to touch each other, and these two sort of slide towards the first setup-" Senku paused for Chrome and the newly arrived Suika's oohing and gasping. "-so the way magnets are pointing matters. Atoms don't really point each other in the right direction, in fact I think calling them magnets is slightly misleading, as I said they make electric fields, but electricity makes magnets, because they're absolutely tiny, weak, and don't really make much of a field on their own. However when they cluster they can actually form magnets by letting their electrons move in a more open space of a a unit instead of a atom. This is pretty rare, as it doesn't really help with anything, but it does happen. Actually, water does this! It's units are tiny three-atom molecules, and as such tend to be really incapable of much, but them being magnetic is why water forms into droplets instead of just falling apart! However magnetite and ferrite, what these are made of-" Senku held up the magnet's and then continued. "Have larger crystals the can turn all at once. They can be pulled because the electrons can flow in alignment with a magnetic field from wherever, and that lets it be pulled! Stuff like rocks can't though, because their structures just hamper electrons. How atoms normally connect is by sharing electrons, but they don't get shared by more than a few atoms, and so don't really do much, and won't get pulled."

"That makes so little sense." Chrome said as Senku finally finished with his copper, presenting a lump and some wire. "So what sort of electrons does that flow?" Chrome said wondering what an electron was.

"Normal electrons, electrons are all about the same. However copper lets electrical current flow! It's a way for electrical fields to get extended from one place to another, which, if we can make a big one, can be used to do work! It's called electricity!"

"Please use less weird words Senku!" Suika said, tearing up a little. "Suika can't follow what you're saying at all!"

"I mean you don't need to learn any of this. However!" Senku said, jumping up. "It's manual labor time!"

Chrome groaned.

"Don't worry! What I need from you isn't too hard! You just gotta find me more copper." Senku said, offering an example crystal of copper ore, which Chrome turned down.

"The expert science-using sorcerous stuff-finder has that covered! I'm off!" Chrome said, snatching a sack from the hut and dashing away.

"Suika, you get to choose." Senku said, snatching a hammer. "Either use your detective skills to find the greatest builder in the village, or you learn to hammer copper into thin sheets."

"Suika wants to do both!" She said, jumping in the air. "Suika guesses she'll learn to hammer, cause' she already knows who the greatest maker is!"

"You do?" Senku said, scared she'd go into hero worship mode and say him.

"Yeah! Kaseki made every house since I can remember and probably an 'illion years before that! And he made the bridge! And he makes stuff like shields with uh, uh, liqueur?" Suika said excitedly.

She probably meant lacquer, Senku thought."Well, he sounds like a perfect fit! Now let's smack this copper!" He said, waving his hammer a little lightheartedly.

Chapter Text

Senku was working on the generator, the first copper disk was ready, and the frame he'd made of bamboo. He wasn't yet sure how to get the disks to spin at full speed, but he'd work it out. Suika had just left to go get this Kaseki guy. Senku took a string from his shirt and hung the disk on it, and placed it in between the magnets. He spun it up absentmindedly. The magnets would be rotated once he got a second disk, but for now the could still make an electric potential. He went to spin it again and grabbed two small lengths of copper wire. He touched one to the disk edge and another to the center, and licked the other two ends. There was definitely some current, but not enough to do much, it wasn't even really painful. Senku looked up to see Kohaku and Tsukasa staring at him.

"Why are you licking copper strings?" Kohaku said, Senku's sanity seeming as silly of an assumption as ever.

"Is there actual current in that?" Tsukasa said, staring almost in awe, and mostly in confusion.

"Yeah, barely. If the disks were ten times bigger and the magnets were twenty times stronger and the friction was one tenth as annoying we'd get a powerful, high voltage current ten billion percent, but it's probably not even a AAA battery right now." Senku sighed, and began wrapping copper wires around the magnets absentmindedly.

"So, we got the sand and seaweed and stuff, if you plan on explaining what it's for more than you've explained electricity." Kohaku said, depositing tens of kilos of shells and seaweed, to which Tsukasa dropped the ridiculous amount of sand he was carrying.

"Get more sand." Senku said, waving them off.

"WHAT?" Kohaku screeched.

"Glass is mostly sand, so it makes sense we'd need more. Come on Kohaku, Senku knows how much we'll need." Tsukasa said.

"Byee-" Senku said as Tsukasa dragged off a grumpy Kohaku. He stuck some wires through the frame to hold them in place and connected them to the magnets, hopefully electromagnetizing the generator, and maybe even making the magnets stronger. He spun at it while touring Chrome's mineral collection until Suika returned with a short old man. "Hey, Suika, is that Kaseki?" Senku said, waving.

"Yes! Suika brought grandpa Kaseki out here!" She said, grinning.

"I have no clue why this little brat brought me out here, but she insisted it was important." Kaseki said, grumbling.

Senku grinned, and spoke up. "Alright grandpa Kaseki, watch this!" Senku grabbed a pile of obsidian from the shack, and shoved it in a small clay kiln he'd built while he was waiting for stuff with his unfinished generator. He shoveled in some coal, and lit it up. "This'll melt and produce an insulating foam!"

"Hmm, do you know what kind of mud it'd be equivalent to?" Kaseki said, scratching his chin.

"What's an insulator?" Suika asked.

"It holds heat in or out." Senku responded to the youngster's question, then turning to Kaseki. "Probably better than any mud, but mud with straw and air pockets in it can get quite impressive insulating properties."

"Would it be suitable for houses? I was thinking about improving the insulation of the houses this winter. Issue is a well insulated house can't really have a fire in it without producing extra deadly smoke. Wonder why." The craftsman said, still scratching his chin, even more furiously now.

"I'd assume not, but we could totally make aircrete by winter, and that's an incredibly good insulator we used 3,000 years ago all the time, and it only really needs some pumps, baking soda, and concrete to make. Along with lots of water and air." Senku said, shrugging. He proceeded to take the now foaming obsidian and spread it across the kiln. "This will cook our glass. One second I gotta go grab some cinnabar, we'll need some lead to make the glass."

"What's cinnabar?" Kaseki asked, now scratching his head.

Suika jumped up and raised her hand. "Suika knows! It's a funny rock that makes weird stuff when you cook it! Senku said it'd kill me if I breathed."

Kaseki starred aghast at Senku returning from the hut with a funny rock. He gasped when Senku threw it in a clay jar and went to put it over the fire.

"Oops, we don't make lead til towards the end. When I do get around to cooking this stuff try to hold your breath, it can be somewhat lethal." Senku chuckled, ignoring how terrified Kaseki looked. He put down the bowl and grabbed a pile of silicon sand. "This stuff is the main body of the glass. We put 70% sand, 20% roasted seaweed, and 10% calcium carbonate."

"Huh this is a weird and complicated material." Kaseki mumbled.

"Now we add the lead!" Senku exclaimed, popping the cinnabar over the flames. "No breathing!" Kaseki backed up and Senku finished cooking the cinnabar, and dumped the lead into the glass mixture. "Breathing legal again. We just pour this  into these two small molds, and we're almost done!"

"Wow, it's completely see-through, like water!" Kaseki said, and Suika squinted at it.

"What's that mean?" She asked.

"Well, if i hold it up like this, you can see Senku here, even though the way for your vision is blocked!" Kaseki proudly said, picking up the still quite hot glass, causing Senku to gasp at how incredibly tough and calloused the man's hands must've been.

"Suika can't see Senku-san through it, it just looks shiny." She said, starring right at the glass. "Suika must just be broken."

"A person can't be broken, that's silly!" Senku said, laughing. "You might, however, have some eyeball issues!" Senku then snatched Suika's helm of melon away from her.

"Hey!" Suika said, going to grab it back but entirely missing.

"YOU'RE ADORABLE!" Kaseki said, oohing.

Senku gasped as well. "Yeah she is! Why'd you hide behind this mask all the time?"

"Because Suika can see even less without it, and she squints up all funny-like, and looks ugly!" Suika then proceeded to squint intensely, and honestly grotesquely, just to make out the ground. "Suika has the fuzzy sickness."

"That's what K- uh, someone else, called their nearsightedness, hm. Well then we don't have to wait for him and I can use these lenses for you!" Senku ran into the hut and got out the corundum. "This material can polish the glass to the shape we need, but I'm not doing it manually, so I'll make a device for it." Senku grabbed some string and a few pieces of bamboo to make a rod that could be spun back and forth like a bow-drill fire-starter. "Kaseki, give it a try!" The old man grabbed the strings, and suddenly his shirt flew off in an explosion of pure muscle-power, reviling an unbelievably ripped set of, well, every muscle on the human upper body. Needless to say the corundum tip was moving incredibly fast, though the bamboo used in the rest of assembly started to smoke, and catch fire. Senku stared at the old man's chest that could rival Tsukasa's. "Dude. What the hell."

"If you're wondering why your amazing polishing machine burned up like that, it's because you're a terrible engineer and forgot about the rubby-force." Kaseki calmly explained, blowing out the fire, and beginning construction of a second machine.

"No!" Senku squeaked. "It's because you're stronger than a pack on lions!"

"Have you ever heard of the margin of safety?" The apparently body-building craftsman asked. "Your design should have some redundancy, or at least a comfortable margin into the abnormal. If you fail to do this, well the rubby-force is a harsh mistress."

"What's a mistress?" Suika asked, still searching for the melon, that happened to be sitting on the floor near her.

"Nevermind." Senku quickly said. "I assumed that I was putting little work into this and therefor probably didn't have to insure it'd handle abnormal effects. Also it's called friction, not the rubby-force. It's cool how many concepts of modern engineering you've figured out on your own but I'm never going to be used to your weird terms."

"HAVE YOU NO PRIDE?" Kaseki screamed. "Each and every creation of yours should be like a child! I cherish homes I built twenty years ago, not because I put plenty of effort into them, but because I love them! I make them to last a century if possible because I want them to live long and healthy live helping the villagers!"

"I mean that's fine for a craftsperson who makes quality goods and stuff but I'm just here to advance technology." Senku said, shrugging.

"Barbarians." Kaseki shook his head. "Anyways the polishing machine is done, though I'd like to oil it up, do you have any blubber?"

"Just hand me that pot and go grab some seeds and nuts from Chrome's secret snack stash in the hut." Suika, having found her melon, jumped off before Kaseki could do it. Senku balanced the pot on the copper disk for his generator, and put that on a spherical rock. "Copper won't burn, so friction isn't an issue." He crushed up the seeds and nuts into the bowl, and spun it up, extracting some very impure oil. Kaseki greased up the polishing machine and gave it a spin. Even with his astonishing full power it didn't warm up or burn, and it was incredibly stable. Senku scratched some shapes on a tree and stole Suika's mask again, asking her to identify the shapes. She failed, and Senku got polishing. About an hour later Tsukasa, Kohaku, and Chrome showed up to watch Senku finish the second lens.

"Suika You're so cute!!" Kohaku exclaimed when she saw Suika without her melon. "Why do you hide your face all the time?" Suika tried to look at Kohaku and the reason became obvious.

"Suika's bad at seeing, but the mask helps and hides her weird squinting! But Seknu's gonna help her see better!" Suika said, then pointed at the tree. "With the glassy lenses Suika can tell apart the triangles and squares! Even Mr. Circle!"

"That's awesome Suika!" Chrome said. "Science is so powerful, it can cure things like the fuzzy sickness and whatever Ruri-chan's got! I'm proud to be a science-user!"

"Alright, Here we go." Senku shoved the lenses into Suika's helm, and popped it on her head. "Now open your eye's and turn around!"

Suika spun, and opened her eyes. She gasped. "Kohaku! You're beautiful! Chrome! Your headband makes you look like a girl! And the copper you got is a funny color! Tsukasa, your hair is so cool! Grandpa Kaseki your arms are scary!" Chrome made a scoffing 'huh' sound. "But- but Suika want to see the science-user who fixed Suika's eyes! Senku-san, she can see what you look like!" Suika turned around, and Senku noticed she had some tears dripping from her melon. "Senku! Suika can tell apart all the symbols on your shirt, one day- one day you'll have to teach Suika what they mean! She didn't even know they were anything more that a funny fuzzy spot before, thank you Senku! You made Suika able to see everyone!"

"You're welcome! Now we do it again for Kinro! Someone go fetch him!" Senku said, and Suika jumped up.

"Suika want's to see everyone again! She'll go get him, and see his face!"

Suika ran off, and Tsukasa and Kaseki turned to each other, and started discussing workout and diet tips to build the most muscle possible without sacrificing mobility in Tsukasa's case, or dexterity in Kaseki's case.

Senku began cooking up some more glass, and Kaseki Informed Senku his kiln was "terribly made" and began slapping together an improved model. Senku, though, didn't wait and just finished making the unpolished lenses. Then Suika dragged in Kinro, with Ginro trailing behind.

"I don't need your science. I need to go back to the bridge, because it seems my brother followed me instead of doing his job." Kinro said, and turned around.

"Kinro, stay please!" Suika said, and grabbed his hand. "Suika has the fuzzy sickness, and Senku fixed it! Suika can see your face so well now! She wants you to see everything well too!"

"Grown men don't need excuses, I'm very happy for Suika, but I'm doing just fine." Kinro said, though he stopped walking away.

"Kinro, you dumbass." Kohaku said, slapping him. "You know what I think of excuses? I think you have no excuse to now use a spear like a spear! You go for silly shots with you lance, all the time! If you want to say you don't need this, then go for actually good shots."

"Kohaku, go drag my brother back to the bridge, and keep the village safe. I'll try these science lenses and if they make me fight better I'll keep them and pay Senku for them." Kinro said with a groan.

Tsukasa made a small cringing look and then shook his head, and spoke up. "Payed healthcare is a nope. You won't give Senku anything."

"Yes I will. It'd be unfair otherwise." Kinro said.

"Senku, return anything he gives you." Tsukasa said.

"Got it." The scientist said to which Kinro rolled his eyes and started thinking of what could be given that wouldn't be returnable. Senku began polishing the lenses and figuring out the refraction needed for his second patient.

Chapter Text

Kinro caved eventually and Senku put the lenses in the wire frame, and Kinro bowed, and went back to his post to think about how to repay him. Senku then got back to working on the generator. He used the copper Chrome brought him to make a second disk, and arranged them side by side. Kaseki Made a system to allow the disks to rotate quickly, using small glass beads as low tech ball bearings, with fish oil from the village as a lubricant this time. "Kaseki's help was definitely great here, I mean it spins way fast!" Senku said, manually spinning it absentmindedly. "Issue is, even with this incredible speed, this'll only produce a small amount of power, so we'll need batteries to store the power."

"What's a battery?" Chrome asked.

"A battery holds electrical power in chemical form." Senku explained. "Electricity turns one chemical into an unstable form, and when you want to release it it stabilizes again and releases electricity."

Chrome nodded, still unsure on how atoms and chemicals and stuff all worked. "Huh, so what do you need to make one?"

"Lead, and containers. With glass and your knowledge of where to find cinnabar and gallium we've got both. And a suitable electrolyte." Senku said, and grabbed a bit of iron from his large rod of it. "Kaseki, heat this up in the kiln until it's red, hammer it into a blade shape, and make a good knife like Kohaku's, just with this iron instead of flint or obsidian. I'll need you to carve these things called gears out of wood and I don't think flint could make super precise cuts." The craftsman nodded.

"Senku, what's an electrolyte?" Chrome said, and Taiju responded before Senku could.

"Aren't they in Gatorade?"

"Yes, they are, but the electrolytes we need won't be found in salty sports drinks, it's sulfuric acid." Senku said.

"Where would we get industrial chemicals like that? Volcanic springs?" Tsukasa said. "Though doesn't SO3 react with water or something to make sulfuric acid?"

"You are correct on both accounts!" Senku said, grinning and duly impressed. "Ten billion points to you!"

Tsukasa downplayed his ideas, but was still surprised he guessed it correctly so quickly. "The second idea wasn't a potential manufacture process though, I have no clue how to get SO3."

"Well, that's where the first idea is double right, if you let saltpeter, found in volcanic environments, decompose, it'll make SO3 by oxidizing, then we steam it to get that sweat, sweat acid!" Senku explained, cackling. "Alternately, we could just find some not super concentrated lake of the stuff, though if it's in a depression in the earth it'll be a literal death trap. Would be much easier to get large quantities though."

"A death trap? How?" Chrome asked, slightly miffed at Tsukasa's science knowledge.

"Sulfuric acid will melt through your skin, pottery containers, and gloves." Senku explained, causing Chrome to gasp. "That's not the main danger though, the main danger is sulfur dioxide. Sulfur dioxide just kills you instantly, and it mixes with the air itself."

"WHAT THE HELL? How're we supposed to get this stuff if it'll kill you, and melt through anything you use to carry it?!" Chrome exclaimed. "We're doing the first idea, the decomposing salt Pete one then. We can mix SO3 with water when it's time to use it, then before the sulfur dioxide stuff gets into the air we can use it up."

"I mean those are all good points, but you're forgetting that if it's not in a depression in the land there'll be little sulfur dioxide, and that while pottery containers would probably leak from the damage the acid would do to them, glass is plain old immune!" Senku said.

"Containers made of the clear vision fixing material, now that's interesting, I'm going to make one now!" Kaseki said, grinning, and grabbed some sand. "Senku, you have any tips?"

"Try using a tube of iron and blowing the glass up while it's molten, then using tongs or something to manipulate it. You'll figure it out sooner than I could, you're crazy skilled." Senku said, sand then turned to Tsukasa and Chrome. "I think we'll do both. Try and find a safe lake of the stuff, but work on artificial sulfuric acid anyways."

"I'll get sulfur from the springs tomorrow when I go to get more nitric acid, and I'll send it back with Kohaku though, because she'll be back sooner." Tsukasa said,.

"Actually, the it won't oxidize without nitric acid, so you'll need to bring that back before we can use it, so you can just let Kohaku take the spring water, it won't matter if we get it a day earlier or not. Also don't resurrect anyone this time, there'll most likely be extra to make nital but  just to be sure." Senku responded, and then ran into Chrome's hut. "Actually, I'm coming with you!" He returned holding a tuber or thready thing of some kind and declared it was silver.

"Huh?" Chrome was quite sure silver was a shiny color.

"Yeah! It's silver!" Senku exclaimed. "We just heat it up, it'll make silver like cinnabar does for lead." Senku started to heat it up, and soon had a little pile of molten silver. "Now we'll stick this on the end of a stick and it'll become a sulfur detector!"

"A metal, on the end of a stick... huh." Ginro said, having returned from guarding the bridge, sneaking away as soon as his brother had returned to cover the duty. "Like could a silver lance be made?"

"Totally! You want one?" Senku asked.

"Sure!" Ginro stuck his lance forward, Senku took it, dipped it in the silver, and gave it a second to cool. "You'll be our death detector!"

"Death? I heard kill you and assumed only science people will want to touch that stuff!" Ginro exclaimed, jumping back from his own lance.

"Well, you don't have to touch sulfuric acid, but sulfuric acid can poison the air. Silver turns black when it's exposed to that poison air!" Senku said, quite excited by the prospect it seemed.

Senku tasked Chrome with finding large quantities of several minerals so Senku could make a surprise for Kaseki, including lime, silica, silica, more silica, and rusty red iron ore, as well as maybe some silica. Then he, Kohaku, and Tsukasa set off, dragging along Ginro who was not happy about this.

Gen had been prevented from crossing the bridge to what looked like small village, spread across two islands, by a black-haired very straight laced guy who identified himself as Kinro. Eventually he left, but Gen didn't want to risk being arrested in whatever these people thought of as a court system. He decided to go check in on Minami. He found her sitting at a small fire, and he asked her where she planned to sleep that night.

"Well, I mean there's blankets here that Tsukasa made out of hide, and there's a fire, so... here?"

"Those 'blankets' smell like smoke, burnt, and ash, someone used them in some form of cooking." Gen said, wondering where he'd sleep that night. "Well, looks like I'll have to earn the villager's trust by tonight so you've got a nice place to sleep over the bridge, and me too I suppose."

"Why would you do that for me?" Minami asked.

"I'm not." Gen shrugged. Minami scrunched up her brow. "I don't plan on sleeping in the hut that the people from out time didn't even make apparently. It's probably going to be stuffed anyways. I just don't see how it'd be any harder for be to help you, and why would I choose to not help someone when it provides me nothing? That'd just be dumb, unless I had something against you, which I don't."

"Sounds like taking entirely too many steps to being what is essentially altruistic." Minami instinctively went to find some paper to write notes on, but faltered, obviously not having any.

"I mean I basically prioritize myself above others, but I'm not malicious, that'd be silly, I just prioritize others below myself. If I could get a bottle of Cola for it, I'd probably kill you here assuming you wouldn't just beat me up, but if not, well, I'd prefer to have a friend."

"Why was your example Cola of all things?" Minami asked.

"I really, really, miss Cola."

Minami rolled her eyes.

"Well new guards are here to prevent us from talking with the villagers, so I'd better befriend them." Gen walked over to Kohaku and Ginro, and waved. "Hey, I met you briefly earlier, I'm Asagiri Gen, I'm not entirely caught up on the policy about not letting some people into the village, the last guy instead of explained said that rules are rules."

"Heheh, he's like that." The guard less enthusiastic about being there said, leaning against the pole holding the bridge together.

"You can't cross the bridge because before we met the folks like Senku, Tsukasa, and you we weren't aware of people from elsewhere who weren't exiled criminals." Kohaku, the scary one, Gen noted, explained. "I mean there's little reason you can't go in to be totally honest, but the people in charge, who are largely quite silly, tend not to come out here and so only know you as crazy people, which isn't wrong, but also isn't the whole story. Still not letting you in though, Kinro is correct that rule's are rules."

"Well I suppose both the policy, and the decisions you and the chief are making make sense given the information he's got, but it is quite silly how closed he is to new information." Gen said, with a small chuckle.

"Well his decisions aren't often sensible anyways, when I tried to give my sister some ramen, she's sick and it's soup so I assumed it'd help, so, my father made me throw out all the noodles, and test the soup for poison, but didn't just assume Senku could make a poison that took a while to activate  and made me throw out the whole thing. He must've just disliked it cause it's new and he's silly and conservative."

Ginro sorta scrunched his nose up and his eye twitched. "Only Kohaku would ever be so critical of the chief. She's also missing how most people think you're weird, that's probably important."

"How... Where would you find ramen?" Gen said, starring slightly to the left of Kohaku's eyes.

"Senku made some. If you can get him to make more I'm sure everyone will get closer to tolerating you people." Kohaku said with a shrug. "And us warriors wouldn't mind, it's quite good, and nutritious."

"I guess I just learned that not only is Senku a madman, but he'll make some great food, and thirdly, I guess I learned food is science." Gen said, nodding, and very much looking forward to whenever he could convince Senku to make him some ramen. "Wait, registering stuff after you mentioned ramen, is your sister the Priestess and your father the Chieftain?"

"Yep."

Gen nodded and raised his eyebrows. "Also that the law only says I can't cross the bridge?"

"Don't know it exactly, but I'm sure if you made it over without the bridge they'd be kind enough to specifically amend the rule to make it illegal and throw you out instead of killing you or punishing you otherwise."

"Well, thanks for the help, you two have been great, I'll try and get Senku-chan to make us all some ramen as soon as possible, heh." Gen walked away with a smile, then waved over Minami and told her they needed a boat. Minami did not appreciate his "lack of sanity" but told him to ask Kaseki, which he did. This tiny old man he found after asked around for that name just grabbed a small tree by hand, despite being, as said, a tiny, probably weak, old man, and took it down to the beach. Then he just started chopping it up, and made two canoes, and placed planks across them to make a rowed, cargo transporting, double-canoe. Gen was ridiculously impressed and asked what the crazed old man would need as payment, and he simply told him to treat it nice, and that he just enjoyed making things.

A few says later Senku, Ginro, and Tsukasa got back, late at night, and they all went to the science hut and/or the village to sleep.

The naxt day Senku got up early, and he told Chrome what the materials he'd found were for. "So the idea of how concrete works, is that you take lime, which has calcium in it, and some aluminum or calcium baring clay, and some other stuff, and you deep fry it while spinning it."

"I don't see how frying clay and those rocks would get you a bad tough material, I mean when we heated up clay on accident making iron it just got brittle, and brittle isn't strong, it was weaker than just rocks." Chrome said, thinking hard. "I suppose it's the calcium, that's one of those atom things, and it's gotta be the secret."

"Sorta. What happens is the cooking does lots of chemistry to it, making really cool compounds out of the calcium, which grab stuff when you putt water on them, causing it to grab all the other materials, and make a mess, that when it dries out is basically doing a group hug but then the water left and it became solid again and. It's like if me and Taiju and Yuzuriha were all hugging when the green light came and stuff." Senku explained. "There's about two issues involved in making it. First is we have no aluminum, and there's not enough in East Asia as a whole to fix it without heading to Singapore or most likely just biting the bullet and going to Australia, as it's not much farther. Second is we'd need a kiln that could spin. The plan I've got for the former is to ignore it and make some lamer concrete, and the plan I've got for the later is to make one with the magic power of Kaseki, just unsure of how to spin it."

"Sounds like a plan? I'm slightly concerned about a heat source that could spin like that but my head already has ideas for getting a stationary bunch of coal working. I'll also think about how to spin this. Even our smaller glass kiln you made and Kaseki religated to cooling was pretty big, I don't think even Taiju, Magma, Tsukasa, and the brothers could spin it for very long, and if it's anything like iron, that'd just not be enough time. The only things I can think of that move constantly with the power to move big rocks, which is essentially whet a kiln is, is the tide, which can't be predicted or spin stuff, and the river, to a lesser extent, which can't spin stuff unless it's a bit of driftwood acting funny."

"Hydropower it is then! Great thinking Chrome!"Senku exclaimed, jumping up with a super wide grin. "Do you know how gears and wheels work?"

"Huh? I was just spitballing. I guess no? I know round things roll downhill and that you need detail to make a gear, but I don't even know how gears work."

After Senku finished explaining gears and wheels and specifically how waterwheels work, he and Chrome walked down to the bridge where the small procession of Kohaku, Suika, Kinro, and Ginro were crossing the bridge. However, at the same time Gen and Minami walked up from the beach. "Where'd you two sleep, the shore?" Senku asked with a scoff.

"Secret reconnaissance program thing-" Gen said with a small self-deprecatory scoff. "I'll tell you later, you'll be interested."

Minami rolled her eyes a bit and asked Senku if he could make paper and pencil or perhaps a camera. He told her to use bark and handed her one of his charcoal pencils.

"Alright, so general briefing on the chemical finding mission. Uh, good news, we found it!" Everyone cheered a little bit, then Senku grinned manically. "Then Ginro almost died going to see it. It was very much in a depression in the land, all that deadly gas. We all almost died, it was quite exhilarating actually." Everyone seemed downed, most of all Ginro, though not about almost dying, almost = who cars after all, but about his spear. Black was lame color. "Don't worry though, cause we also got lots of nitric acid and piles of sulfur, so we'll be able to make loads of it artificially, it's just kinda lame to waste nitric acid on this. I'd much prefer to go get the stuff from the lake but that'd involve testing gas masks with lethal gasses, which is, uh, suboptimal. We'll stick to the artificial stuff for now, we're lucky to have that nitric acid."

Chapter Text

Senku went back to the science hut to get on making those chemicals and found Keseki had beaten him to it, and had set up a display of at least a dozen beakers, ampules, and vials, as well as a large decorative vase. "Whoa, you're great at this Keseki! It'd take me weeks to figure out the technique for this and you did it in two days!"

"Of course I figured it out Senku! It's quite like clay, just, upside down, and you blow in it, and it burns you, and other stuff."  Kaseki said with a shrug.

"Well, now that I've got chemicals, chemistry to do, and thanks to you equipment to work with them, I'll need a lab!"

Kaseki chuckled and grabbed a flint axe. "How big will this funny named building need to be? How well insulated? What sort of foundation?"

Senku thought for a second, happy with the old man's enthusiasm, then responded. "Nothing fancy, single room home mostly, I'll just be using it for science. Actually we ought to make another building for Taiju, Yuzuriha, Gen, and Minami anyways. there isn't much more room in Chrome's hut for anyone other than me, him, and sometimes Tsukasa when he isn't running around in the middle of the night like a fox."

"Well I'll have my work cut out then! I'd better go gather some lumber!"

"No need!" Senku chirped out. "We've got Tsukasa! That maniac will just punch the trees out of the way, or use his giant spear thing if he's feeling fancy. And then Taiju will carry whole trees back to you."

Kaseki went and started making the buildings and Senku went to talk to Gen ans Minami, who explained they'd spent much of last night hanging out with villagers across the bridge, and Minami was actually slightly hungover. Senku instructed Minami to get in touch with Ruri, the priestess, and what to ask her. He told Gen to get her trustable enough to talk to the priestess and generally get the villagers to like the modern-timers who used science more.

As soon as the lab was finished Senku started moving his stuff in, and began mixing some chemicals together and burning things. Senku put the burning stuff over a clay bowl of water and all of that over a fire. He called in Chrome and they brought in all the concrete ingredients. "What's that?" Chrome asked pointing to the burning stuff, now enveloped in steam.

"Burning stuff makes other equally useless stuff but the second stuff happens to turn into cool sulfuric acid when it reacts with water, and steaming the fieryness makes it a one step process." Senku explained, then turned to the concrete materials. "Uh, this is useless until we make one hell of a kiln. It won't really need to spin. That'd be nice, but I don't think we're able to make something that'd hold together like that. If I remember my adiabatic flame temperatures correctly coal can easily get hot enough, but it'll take some crazy amounts of air."

"So my awesome idea of using water to spin it will go to waste and we'll need to work even harder pumping bellows?" Chrome exasperatedly said.

"Well, we have a solution without a problem, and a problem without a solution. What do you think we should do?" Senku asked.

"Uh, use the gear and wheel stuff you explained to me to make the water somehow work bellows?" Chrome said, quite confused, unsure how to make rotating into pushing aside.

"Well yeah, so let's go draw up some plans and make Tsukasa and Taiju get more wood now that they're done getting wood for the buildings!" Senku said, jumping up and checking on his sulfuric acid. "This is exhilarating, hydropower in the stone age!"

"What's the plan really then?" Gen asked Tsukasa, after explaining to him his plan to get chummy with the locals.

"We're making the sulfa-based antibiotics for the priestess of this village. We really need to have a good conversation with her because she apparently knows about things like why the village is named after Senku, something about his father's grave, which is apparently nearby despite his father dying in space three thousand years ago, and potentially allowing us to brute force getting the villager's to like us via her being universally loved." Tsukasa 'concisely' explained.

"Hmm, anything I'd better do or should I continue fucking around?" Gen asked.

"I saw vinegar on the to-do list, so probably get any wine or spoiled wine you can." Tsukasa said with a shrug. "You'll honestly do best to 'fuck around', it seems to get a lot done."

"Alcohol, you got it." Gen said, nodding with a grin. "I could never drink the stuff, but I'll get it anyways."

"Wonderful, I'll go check in on Senku to see what he needs, see if you can do much more."

"Tsukasa asked me for a brief on our progress, and uh, I told him to fuck off, which obviously aggravated him, until I explained that the rest of you lot are probably quite lost as well and I should probably just tell everyone everything." Senku said, calmly waving around copper wires and gears Kaseki had been making him. "The general state of things is about this: we've got the stuff, but not much and also we need to figure out how in the hell to get this stuff to Ruri, because no one, even the villagers, will be permitted to walk up to her and give her weird stuff." Senku grabbed some bamboo, thew it out, grabbed some rocks, and got back to fiddling with his gears and wires. "First step is a huge, powerful, permanent kiln. This will solve the big issue that we have like two pieces of iron and have to build a whole bloomery and make ramen every time we want to make another, it will also allow us to heat some iron well beyond it's curie temperature, which if done to pure ferite, an easy enough task, will allow us to make an industrial strength magnet or two, which will be killer for electrical power, which we simply don't have an industrial amount of of. I'm considering some fun infrastructure projects after we finish the sulfa drugs, which will not only make the villagers like us, and Kaseki will love, but it'll get Tsukasa off my back about being selfish, and if that's not a selfless reason to do stuff, I don't know what is."

Tsukasa scoffed. "You're really not doing yourself any favors."

"Whatever."

Chrome rolled his eyes at the two of them "So, what do you need from us,master science-user?" He said with a grin, crossing his arms.

"You need to get Suika to teach you how to flatten copper, then make copper disks as big as humanly possible." Senku said, causing Suika to giggle, probably enthused about being helpful. "Tsukasa and Taiju, you need to get Kaseki whatever he asks for. And Kaseki?"

"Yes Senku?" The old man asked.

"You need to make me a water wheel and a shitload of gears. Here's the schematics. You have a week. No one rush it, but, uh, don't loligag."

"Senku, am I just a decoration to you?" Yuzuriha asked as politely as such a passive aggressive question could be asked.

"Yeah, that." Kohaku and Kinro said, while Ginro seemed fine with not working.

"Well Kohaku needs to start doing Tsukasa's job of getting the nitric acid, and I've got two jobs for Yuzuriha, first, I want paper by the end of the week, and second, you'd better figure out glassblowing, we'll need vacuum tube sooner rather than later, and I don't want the old man to die of arthritis." Senku said to Kaseki's unenthusiastic grumbling, mostly about his extreme capability. "I'm trying to think of what the brothers should do, maybe-"

"Wait, I have an idea, I'm the head of state after all, right?" Tsukasa said, his imposing figure calmly standing behind Senku, though he wasn't anywhere near the scientist before.

"Hm? Okay, like what?"

"Like I think this people's republic of science needs an army, and myself and Kohaku isn't an army."  Tsukasa said blankly.

Senku grumbled about how clunky people's republic was in all scenario's while Ginro said he was "totally army material" and that this was an "insult to his masculinity."

"I know a warrior who could kill an army on his own, who doesn't have enough strength for you to need, Senku, and who already is wonderful with spears." Tsukasa said, glaring at Senku for the perceived slight to his nation name idea. "He'll work wonderfully with the brothers. We'll get an army in no time, though I'll also need this new furnace to make steel spears. Also, Senku, if you don't like People's Republic, what do you like?"

"Kingdom." Senku said, quite calmly for how much the suggestion immediately ticked off his co-leader.

"Never. I am not a king."

Senku rolled his eyes again. "I won't live with a stupid name like people's republic, so what then?"

"Well then how about the full name is the Pure Democracy of Scientific Progress, but you can call it DoS⊆P, like with an invisible 'is contained within' symbol like from set theory to notate the P's surround the DoS." Tsukasa said, rolling his eyes.

"Sure. We'll call it the democracy of science though, DoS⊆P is a good abbreviation but also sounds weird and/or stupid."

"That was mostly a joke, but whatever, sure." Tsukasa said, grumbling slightly and relaxing now that their state wasn't going to be a fucking "kingdom."

"Now, I'll we explain waterwheels and how to drive bellows with rotation, you'll all probably not know this one, but this is how to make a Reciprocating Rack and Pinion!"

Hyoga woke up, finally. He'd lasted who knows how long? A week, three thousand years? However much, it hadn't been enough, he'd lost consciousness, maybe died, but he was back. He went to breathe, and found he couldn't feel his nostrils. He back was the only part he could really feel, so he flexed it, feeling the, well, feeling, spread across his body. Something was surrounding him. He slowly pushed though it, and his perception of time seemed to get back in sync with reality, and he realized this whole experience had taken about a second or two. Hyoga burst from what turned out to be rock, and found himself naked, in front of Tsukasa. "I see the world ended. What did it in then? And why didn't I die properly from it? However long that was sitting in there is not a death is it-" Hyoga then saw the numerous statues around him.

Chapter Text

Two nights after Senku's plan was laid out, Gen was finally invited to a party. The villagers quite enjoyed his company, especially Ganen and Sapphire, who seemed to especially enjoy his stories about the old world. The party though, didn't matter much to Gen, though it was an opportunity. He'd noted how the main reason Sapphire was looking forward to the small celebration, apparently announcing that the Grand Bout (some sort of election or championship) would be in a few weeks, was to find a handsome man. Ganen, as usual, just wanted food, but there was a very slightly immoral side thing to Sapphire's reasoning. He had discovered Sapphire telling her sisters she thought Gen of all people was the most handsome man around aside from Tsukasa, and one of her sisters had called do s on him if he ever made himself available to date. Their list of priority men was kind of laughable, one wanted Senku, an asexual in the most apathetic way, one wanted Tsukasa, who was very clearly not into, well, people, not just girls, potentially ace, almost definitely not straight, at the very least not into people for purely physical stuff, and the last, Sapphire herself, wanted him. Gen had a long list of hating himself reasons for why he'd be a terrible boyfriend of unavailable, but he also happened to be himself, and knew he wasn't interested in her type. There was a side of him that'd just fuck anything cute, but it wasn't a genuine or mentally healthy part of him. Point was, Sapphire wanted him drunk at the party. Gen wasn't drinking alcohol though. Unless someone could make cola, he'd stick to non-drink stuff. At the very least Gen could offer that maybe he'd drink if he could take a barrel or two of wine to his friends, and then get Sapphire to drop it with the normal reasons for why he didn't drink, get the alcohol to Senku, and then maybe lead Sapphire on until he could drop her off.

"Gen, you- you gotta have some of this!"

"I can't Sapphire, alcohol is terrible on me, ruins everything cute about me."

"Cute? You're handsome! Handsome doesn't go away! Drink!"

"Hmm, how about you give me yours?" Gen didn't, uh, really like doing this.

"Hm? Here?" Sapphire tried to give Gen her cup.

"No no! Give me a mouthful of yours!"

"Huh, so not a sip? How then... Oh!" 

Yeah, she kissed Gen. It was reasonably hot but Gen had a plan, and had timed this for right when Ganen walked by. Gen spit it out right at Ganen's feet. "Ew, that was terrible wine! I'm sorry Ganen, here, have an apology wine! Sapphire poured me this cup, but I don't drink anyways." Gen handed him one of the cups Sapphire decided were his. 

"Gen, this wine is pretty good!" Ganen said, downing the whole glass. "What's wrong with it?"

"Nah, not in comparison to stuff from before the petrification!" Gen had spun a girl trying to get him drunk to fuck him into story time for her and Ganen. Ganen, of course, loved his stories, and Sapphire was to drunk to not stare at his lips if available. Gen would have to escape eventually, though that'd be easy enough with Miami being rather sober, willing to plot with him, and with the two people who wanted him being drunk. Point was he'd pulled it off.

Senku was gifted a large barrel of wine from Gen, which had sadly gone bad, though this made Senku exceedingly happy. "What good is the sour, spoiled, wine?" Chrome asked, smelling the acidic liquid.

"This stuff is vinegar! Not only is a great cleaner, but it's an ingredient in sulfa drugs!" Senku explained, then grabbed some small crystals from the vinegar Chrome hadn't noticed. "This is also useful. We'll just brew up some fun scary toxic terrifying chemicals and have the miracle cure done as sure as we can use the waterwheel to power the furnace to make some massive permanent magnets, and the electricity those magnets make will let us make will let us make even scarier chemicals!"

"Huh? Scary chemicals? We're making medicine, right?"

"Oh no, super scary chemicals, kukuku, stuff like analine, clorosulfuric acid, all sorts of toxic stuff that could kill you or Ruri in minutes!" Senku said, laughing like this terrifying prospect was a funny side effect.

"Do you eat sulfa drugs?!" Chrome said, eyes wide with fear.

"Traditionally no, you'd rub them on your skin. When they were first orally consumed you'd mix them with refrigerants, among other things, and drink them." Senku explained, grabbing the sulfuric acid and pouring it in a glass pot to cook it. "In our case, we don't have time for that. Eventually I'll teach you how to make modern pills, but Ruri's a tough girl, right? She'll eat it plain, I'm sure."

"Plain old death chemicals? When that death acids boils, what happens? You get more deadly acid?"

"Yeah."

Chrome groaned. "Senku! Stop making deadly chemicals and make something helpful for once!"

"Okay. Let's get a lid so we don't waste this extra deadly hydrochloric acid." Senku placed a lid over the acidic mixture. "Now let's go fry some seashells and limestone! And sand." Senku grabbed Chrome, handed him some gears to assemble, grabbed Taiju, had him drag the secret pile of concrete materials to the furnace, and grabbed Kaseki and distracted him my giving him the plans to a funny bamboo thing they'd use the new waterwheel to spin. "Now let's cook some cement!"

"How does cement work Senku?" Chrome asked while hooking up the spinning waterwheel to the gears to the level three furnace.

"Well, when you cook sand with the shells the calcium carbonate in the shells becomes sodium carbonate, this stuff is basically already cement, me and Taiju used some for mortar before we met you, but it's weak, and dumb. The calcium now freed from calcium carbonate in the shells and limestone, which already became lime by now, all gets mixed with some glass sand, making a mix of silicon, which is what makes rocks so hard, and calcium, what makes bones so hard. This can get a little iron ore added to it to get some of that iron awesomeness, but without aluminum we don't get Portland cement, sadly."

"Where do you find aluminum? I'm a master materials guy! I can totally find this aluminum stuff, is it in rocks? It makes cement hard, right? Would it's ores look like corundum?"

Senku went from giggling to laughing on the floor.

"I'm not dumb!" Chrome yelled.

"No, you're a genius, but also stupid!" Senku said, still laughing. "Corundum is an aluminum oxide! It just doesn't have enough to do anything, and we won't have the voltage to get it out anyways. The good aluminum ore is in Australia, sadly, and that's across the whole ocean."

"Huh, how long would that take in a legendary, science-powered, well-manned outrigger?" Chrome asked, wondering what sort of terrifying ways boats got stuff done before the stone world.

"To get to the north coast of Australia? Years." Senku said, crushing the materials up with a rock. "I mean an outrigger is suboptimal, it'd go with a great sailing ship, maybe a steamer, able to go against the greatest of winds and battle the very elements!"

"Steam... On a boat? Why'd you take a pot, where'd the fire go without burning stuff, and what good would a steaming pot do?"

"Blow in this piece of bamboo with your hand covering the far side." Senku handed Chrome a hollow tube.

"Okay?" Chrome did as told, and his hand slipped away allowing the air he puffed up his cheeks to get out to escape. "What does that have to do with the ridiculousness of fire on a boat?"

"What did you learn about adding air to a chamber you plugged up?"

"Well I guess that it'll try to not enter somewhere with air already in it if it can help it, and get in your cheeks instead!" Chrome said, throwing the bamboo away and grabbing a basket of coal to start up the furnace.

"What if the plug could stretch instead of your cheeks?"

"Well it'd stretch the plug out?"

"Yep! And what is steam?" Senku said, very happy with Chrome's intellect.

"I dunno? Warm, wet mist?"

"A mist is made of tiny droplets, steam I'd closer to something else, all the individual molecules are mixed in."

"Uh, water? Fire? Air?"

"Yeah, air. Steam is a gas, just like air."

"So if you filled a test tube with water, put bamboo over it, and a stretchy thing over the bamboo, you could heat it and... Make a pushing force until the stretchy thing fell off?"

"Well, usually you'd use boiler tubes, and pistons instead of stretchy things, but the main difference would be how much pushing would be made and the durability of the whole thing, but more of less." Senku said, preparing the concrete in the furnace. "Now think about the thing slipping off. What if I stead of sleeping off we let go of the steam. Let it pull back in, and then push out again."

"You could make a flat gear and attach a round gear, and attach a hand and make it wave?"

"Or attach an oar to it. Or use thing we use to power the furnace bellows but backwards." Senku realized that the villagers might not know how propellers worked. "By the way you can use spinning blades or paddles to move a boat. Actually the whole concept of a steam engine is sorta a backwards version of a waterwheel to power bellows to power a furnace. You use a furnace to power reverse bellows to spin a waterwheel, in a riverboat at least."

"How soon until we can make one of these?" Chrome said, very, very excited.

"I don't plan on going to Australia anytime soon, but an engine? As soon as we need to move a lot a long distance, an engine for a boat, car, or train would make sense."

"I'll find a ton of ores in the caves soon and make you make a car-train thing to get tons of something useful to sciencing from there quick!"

"I mean if you find oil, pure silicon, or anything like that, totally, a train would be warranted." Senku said with a shrug, as Chrome watched the gear mechanism drive the furnace. "Give this a minutes to cook, while that happens lets practice our gear-carving skills and try to get some of the less precise bits needed to spin the tiny generator really fast to make the magnets work."

"I couldn't tell if that was a joke, are oil and silicoonys found in specific places like aluminum, or like anywhere if you're lucky, like iron or rare plants?"

"Oil is found in places that used to be warm, shallow oceans ten billion years ago. The algae that loves shallow seas, those are tiny plants the size of germs, dies without getting eaten by scavengers, and their bodies get heated and compressed into various icky compounds, but one of those is oil. Oil floats up, even through some rocks, so even though most places were shallow sea at some point, there has to be a trap of really hard rock over it, and it can't get too deep, like if a mountain grew over it, it'd get crushed into natural gas." Senku said, like it was common knowledge.

"Huh? That's really weird, mountains don't really grow do they?"

"They do. They aren't alive like plants or anything." Senku said, which confused Chrome. "They grow when two bits of land smash into each other." Senku grabbed his robe, laid a bit on the ground, and pushed on two spots with his thumbs, and moved them inward.

"It's getting crinkled, you gotta flatten it Senku." Chrome said, reaching for Senku's robe.

"No! The crinkles are mountain ranges! The other way mountains pop up, especially in Japan, is that lava bubbles up from the ground, and when lava cools it becomes rocks, and if you repeat that in the same place..." Senku pushed some sand through the cracks in his hand, from the bottom. He did it a few times and pointed out how it was piling up.

"So is there oil nearby? did the tides used to be higher and flood this area? Ten billions years sounds like a lot longer than 3,000 something years, and so weather there used to be oil nearby is probably going to effect weather I waste time looking for it."

"Here? Nah." Senku shook his head. "There's some oil fields near here, but they'd bee pretty hard to find and kilometers that way." Senku calculated his coordinates, and those of the Sagara oil field, and guesed the cardinal directions from the sun.

"Huh. What's oil look like?"

"Black shiny stuff, liquid." Senku said, and fit his first gear into the larger, spinning, waterwheel one. "Don't eat it, or mess with it. If you find it, tell me, and we'll make the proper equipment to get it."

"And silicon? Please give me the short version." Chrome asked, still having no clue how oil works, despite Senku's best efforts.

"I'm afraid my supply is on fire right now." Senku said calmly.

"WHAT? WHERE? WHAT FIRE DO I PUT OUT- WHERE'D YOU GET IT? CAN WE MAKE A TRAIN THERE?"

"Silica sand is silicon with oxygen stuck on. It's an ingredient in concrete, silly." Senku said, cracking up.

"Phew, you scared me for a second. How do we get the oxygen to let go?" Chrome said, panting.

"No way in hell. No way. Not 10 billion percent nope, 0% yes." Senku said, laughing much less happily.

"Come-on! It can't be impossible, can it?" Chrome asked, wondering if it could, in fact, be impossible.

"It's not, before the petrification I had a machine I always kept in my pocket that could think, and it's brain was made of almost 100% pure silicon, and every impurity was a purposeful deviation to change it's properties to make a detailed brain." Senku said, as Chrome's jaw dropped. "I had a few others, but they were used for like math and gaming and stuff. My dad even once designed a mind to live in some brains he tied together. The brains didn't have minds in them you see, you'd have to write any thoughts you wanted them to think, they couldn't do anything on their own. But yeah, if you do the right stuff, you get the pure silicon to make computers on. Brains are called processors, the machines they think for are called computers. That's why I'd immediately start making a train, with help of course, I have twig arms, if you found pure silicon." Senku gave it a though, and honestly he wouldn't be able to do much without years of upgrading to precision production equipment, even if he had infinite pure silicon.

"BRAINS? YOU'RE TELLING ME YOU USED TO HAVE A BRAIN IN YOUR POCKET?" Chrome left, hyperventilating.

"Darn, I hate when people take stuff harshly, like just input the information, store it, process it, organize it." Senku rolled his eyes, and started prepping to take out the concrete and put in the iron, heating it past it's curie point would allow him to use relatively weak electromagnetic fields to align the whole iron rod at once, producing huge magnets quickly.

Hyoga sharpened the flint blade, missing his old spear very much. However, even though he lacked any decent weapons, had weird scars all over his face that felt numb to the touch, and Homura was clearly distressed about the situation, Hyoga could finally actually wield real power. Tsukasa was... an issue. He was smart. Really, really, smart. He had the terrifying mix of the brains to see through morality, and the discipline to have it anyways, allowing him to come up with the most immoral ways to doing things, or the reason one might do such things, but would moderate his actions. He also had the power to do anything on his own, and the charisma to get many people to back him up, letting him have an effective power level of "yes." Tsukasa's idealism was a serious threat. He'd never let a truly meritocratic society form, because that would necessitate stratification (though that was silly, the only people who'd loose out would deserve it). Hyoga would probably just try and support more freedoms, and Tsukasa had already mentioned preventing "weapons of science," which was probably Tsukasa-speak for force multipliers, which would allow egalitarianism to become equality.

"Village is 40-70 people, 5 kilometers past that hill, large building on the farthest of two small islands, several on the larger and closer, three in a clearing on the mainland with different architectural styles than reach other and the rest, and a small waterwheel or something on a river nearby." Homura whispered to Hyoga.

"Yes I see it too." Hyoga responded. "Good eyes." She always did things properly. Hyoga tied the flint blade to the good looking piece of wood he'd grabbed, and started looking for something hollow to put it in. A stone blade would break quickly, but if the chemical Tsukasa had revived them with was in a glass container, a steel or iron one might be available soon.

"Whoa! Senku's gear thingy is so fast! How does it get faster than the river that's spinning it?" Suika asked, watching the gears attached to the waterwheel accelerate the tiny generator incredibly fast, causing the giant electromagnet Senku made to suck up little sparks of iron from where Kaseki was forging the two rods that'd be made into magnets.

"Well, you see on this big gear, how it goes around once every second on this grove?" Senku pointed to a large, wooden gear, coated in lacquer, with a grove at the halfway point to the edge. "It also goes around every second up at the edge, but since the gear is bigger, each part has to go farther in the same amount of time or the gear would get twisted!" Senku tried and failed to touch the edge, it was moving so quick it knocked his finger away. "So then if you put a small gear next to the edge that's only as wide as the ridge, it'll go twice as fast, because each gear tooth has to match another, and the edge gear teeth are moving twice as fast!"

"Suika is kind of confused, but that's so cool!"

"Rod one is ready Senku!" Kaseki said, waving a giant, red hot rod of iron. "You said not to cool it off, what do we do?"

"Quick! Before it cools off, pass it through the magnet!" Chrome said, checking that the ceramic plate that kept the hot iron from touching the wires was secure, and waving the iron rod over.

"Good, good, how that it's through, go cool it off." Senku said, checking that the wires weren't getting too hot.

Kaseki quenched the rod in oil, and placed it on a rock. "Is it a magnet?"

Senku grabbed a chunk of iron ore, and it stuck to the tip of the magnet. "Yep! Now we need that ore back-"

"Don't touch it! I'll use these tongs, the metal is still hot even if it doesn't glow." Kaseki snatched up the ore (with some effort), and threw it in the furnace to smelt it for rod number two.

"Hey Senku, new people Tsukasa revived walking over with him, about a kilometer away." Kohaku whispered to Senku.

Senku had no clue how she could see that far. "Could you tell how many?" Senku asked, wondering if she'd seen that well.

"Tall man, short women, girl made eye contact with me, so she's got good eyes, guy made a spear. Tall girl behind them, blonde, wooden clubs or something." Kohaku noticed Senku's jaw dropping, but continued. "One with funny shoes and a hat, he turned when you quenched the metal so maybe he has inhuman hearing, but probably just coincidence."

"Uh, that's kinda crazy impressive." Gen said, eavesdropping. "I'll go meet them, I am the best at social stuff after all."

Homura spotted a man waiting for their little party, he was small and effeminate, with a robe and no weapons. He waved as soon as Hyoga got close enough they could see each other.

"Hello! Welcome back Tsukasa, Minami didn't give me the details on who you were resurrecting, would you like to introduce me?" Gen said, noticing the terrifying glare the tall one gave him, though it was ostensibly a scanning glance.

"Hello Gen, new people, this is Asagiri Gen, you might have seen him on TV, or seen someone who read his silly books. Apart from his writing, he's quite skilled, and is the most trusted of our number by the villagers." Tsukasa said, and waved over the remaining members of his party. "Saionji Ukyo, sonar operator for the self defense force navy, can tell apart a pebble and a stick being throw into a pond from almost a kilometer away."

"Well that's a wild exaggeration, maybe even a fabrication, heh-" Ukyo quipped, tipping his hat.

"This is Akatsuki Hyoga, we knew each other from some martial arts crossover, but he used weapons in various historic and unsavory things, and I stuck to MMA so this hike has been our longest time together." Tsukasa said, noting Hyoga's cold stare. "Probably the strongest warrior I ever met. Keep him away from his preferred weapon if you only have one army to fight him."

This Hyoga character was going to kill or rape someone. No doubt about it. No one with good intentions looked at the only person who could defeat them (Tsukasa) with such a death stare, like they wanted out from under them, like there was some unsavory restriction Tsukasa had. Tsukasa was too principled for that stare to mean anything good. And either he'd noticed that girl loved him and didn't care, or was oblivious, which was, unsettling. ND very valid, yes, those eyes, nah, too much to chalk up to that.

"Momiji Homura, the only person Hyoga respects." Tsukasa said, turning to the pink-haired girl. "No clue what she does, but Homura must be some sort of demonic powerhouse if she earned Hyoga's trust."

"She just does things properly, unlike everyone else, sadly." Hyoga said,which Homura clearly peaked up at hearing.

"And last but probably not least, Hanada Niki, she's good enough at Judo me and Hyoga had both heard of her." Nikki rolled her eyes. Tsukasa continued. "Also she recognized the notes Ukyo was using to approximating bird noises, so she might be hiding some musical talent, and I honestly can't imagine how helpful modern entertainment would be at winning over the villagers." Nikki blushed, oddly, possibly she'd been torn between Judo and singing or something, Gen couldn't say,

"Wonderful! Here, I'll give you the tour, Tsukasa will probably want to cooperatively lecture with Senku or go on a run after walking so many kilometers." Gen said, waving him off, and leading the group over to see the bridge, hopefully giving time for Senku to learn what Tsukasa had hopefully also noticed about Hyoga, and hopefully understand politicking enough to do something. Hopefully that wasn't too many hopefullies.

Chapter Text

Senku arranged the glass beads on the new cast iron ring's grooves, and squirted oil on them, before welding the two halves of the outer shell on, to form a ball bearing assembly. The copper disks would attach, and be spun at ridiculous speeds. With enough gears the generator would be able to produce extremely high voltage DC current. Senku went to pop it in the assembly with the first full size disk, and saw Tsukasa. "Hey, how'd it go?"

"Good, but also risky." Tsukasa said, and picked up the two meter diameter copper disk and handed it to Senku with one hand.

"Explain." Senku motioned for Tsukasa to hand him the hot soldering iron (like the ones of old, this one was literally just a hot piece of iron).

Tsukasa handed it over. "We got two highly qualified fighters and the best scout in the stone world, and the best guy to help when you eventually make radio or audio technology Minami could think of, but two of them are literal risks."

"Sounds mostly good. What's the issue with the two?"

Tsukasa sighed. "The pink haired girl is completely loyal. Completely and utterly. And she's skilled enough I count her as the best scout, probably able to escape Kohaku, and with comparable senses to her."

"So you're parroting Kohaku's strengths as threats? Imagine what you think about her were you still trying to extinguish science." Senku said with a small scoff, and began sliding the assembly onto a sturdy mount on a frame that already held massive magnets.

"The issue is who she's loyal to. Hyoga is the only person who could kill me without a gun, though he'd still need his favored spear." Tsukasa said grimly.

Senku grabbed some fresh copper and poured it into the large mold. "So someone can challenge you and this is a threat? Anyone with a stabby object could kill me, do I care?"

"Issue is, he might do it." Tsukasa said. "He's got a slightly odd ideology, and his is actually not just antithetical to scientific weapons like mine, but to antibiotics and such. He might allow some progression, but he'd kill a lot of people to keep it safe progression."

"Huh. So make him a teacher, maybe he'll get attached to people cause he taught them how to stab, maybe I have all the ingredients to gunpowder if you give me nitric acid."

"The guards are spear users, and Kohaku can't figure out how to approach spear users for the life of her, so he'd be great." Tsukasa said, watching Senku pound the copper into the perfect shape.

"So I'll have Kaseki make some polearms. Maybe even Katanas for Kohaku! This is exhilarating, the best weapons of the iron age made at the same time as a generator, and the chemistry we need for antibiotics!" Senku said, cackling.

"Sounds like a plan. I'll train on breaking polearms. I noticed the girl who's loyal to him, Homura Momiji, is an acrobat, so I'll have her teach me the mobility she might eventually try to exploit my lack of." Tsukasa said, and grabbed some of the materials Senku needed, offered them, then began walking away. "We'll need to set up a government. A week or so from now the election thing the locals do will take place, and we will get a puppet chief. Concrete is a perfect element for making government building out of."

"I knew you liked those games where you make stuff." Senku said with a small laugh.

"That's- a very large category of games." Tsukasa turned and waved to Chrome, Gen, and the new people walking over, when turned specifically to Gen. "Why don't you let Chrome explain the waterwheel and related things, I have to talk to you for a minute Gen."

"Sound's good, I'm terrible at understanding all the electricity stuff anyways, heh!" Gen said, and walked away with Tsukasa.

Soon they made it to the clearing by the bridge. "Senku's got a slightly mad plan."

"Slightly? Thank goodness, we're avedsay." Gen said, honestly rather unironically.

Pig Latin? Weird. Tsukasa elaborated. "There'll be a lot of combat training. Hyoga will teach our people how to fight with and against spears. I'll learn from Homura to outplay her and from myself how to disarm spear users. Senku will make all the prerequisites to firearms, though I'll prevent him from making any until the last minute. In all honesty there's a chance Hyoga reconciles his ideals with us and we live happily ever after."

"So, what do I do?"

"Just get your relations done. We want a puppet to take the grand bout, scope out the competition, and ruin them. Find out what the entry requirements are, to see if we'll have to go with bad potential puppets like the guards, is Chrome going to be able to take it, or could non-villagers get in?" Tsukasa said. "Additionally figure out what Ruri's cryptic message was ages ago."

"Alright, will do, just pay me in Cola, hee-" Gen said, and walked off, artificially joyful.

"Cola? Now that's a good idea." Tsukasa said, scratching his chin. "I mean ramen is probably sufficiently advanced for most food purposes."

Chrome had cleared away the new arrivals to find out where they'd be sleeping and what they'd be eating. "Now Senku, two issues."

"Yep?" Senku said, quite sure Chrome hadn't picked up on the Hyoga issue.

"How do we spring the concrete surprise on Kaseki?" Chrome asked.

"Well, we'll make some cement, and show it to him!"

Chrome nodded, and scratched his chin. "That's what happens when you add water, right?"

"Yep, when were you thinking?" Senku responded.

"Soon, hmm, how about tomorrow, to impress the newbies!" Chrome said, excited to have a gift for their best engineer.

"Good plan! How about issue number two?"

Chrome got deadly serious. "Explain the artificial brains. Now."

"You'll have to specify." Senku said, realizing he'd have to explain semiconductors without explaining conductors first.

"Everything about the idea! What lets them think? How do they communicate with you? Can they learn, or do you have to write their skills too? How do normal brains even work?" Chrome said, waving his arms about like mad.

"Pick one." Senku said, and finished his generator up with some simple wiring.

"Uh, what do they look like?" Chrome asked.

"Like so:" Senku grabbed a stick, and drew a rectangle. "I have no clue why, but they were always put in somewhat rectangular boxes."

"Well what's it look like inside?"

"How's this?" Senku drew a larger diagram. There was a central square called the CPU. "This does the thinking, but it can't do much other than exactly what you tell it. It'll forget things not because it's unhelpful, but because it lacks a memory altogether! It's usually attached to a little thing called a register to hold numbers it's doing math on, this means nothing has to remind it what it's doing when it needs to do math. After all, the only thing it can do is math."

"It doesn't sound very smart. How do you get complex ideas and stuff in there?"

"Well you have to load in thought from somewhere. This is memory, also known as RAM." Senku pointed to stacked rectangles attached to the CPU with a line. "It's really simple, it's just a lot of switches. The switches represent numbers. I'll teach you how to make numbers out of yes and no questions only later, it's not too hard. Some old computers used normal numbers, but that was really inefficient. The first of these switches were tiny actual switches like ones you flip, pushed up and down with electromagnets. This is slow and makes ten billion clicks a second if you want it to store ten numbers. This is where in-progress thoughts live until your computer is done thinking them. After that, any information you want to keep is sent to the hard drive." Senku pointed to a circular thing, shaped like the copper disks he was spinning up for the generator. "The hard drive also stores all the thoughts you're done with but don't want to forget, or parts of an idea that won't fit in the RAM."

"So the RAM is like the part of my brain that lets me not forget about  a thought while I'm thinking about it?"

"Yep."

"And the hard drive is where my memories live?"

"Yep."

"And RAM reminds the CPU what it's doing?"

"Exactly Chrome! What else is confusing you?"

"How do the thoughts get from this brain to yours?" Chrome asked.

"They don't." Senku said with a scoff. "The messages wouldn't get in anyways and that's just not how they worked."

"Then how did you find out the stuff they thought?" Chrome said, puzzled.

"Chrome, why don't you think about a bird. Now get that thought into my mind somehow." Senku looked away, waiting.

"Uh, uh, here!" Chrome drew a terrible bird next to the computer.

"Perfect!" Senku drew a box around the bird and a line to connect it to the CPU. "This is a screen."

"Explain?"

"It shows pictures. Like this bird. Or the answer to a math question." Senku said.

"Huh. How does only math make pictures? I'm pretty good at math and can't think of how you'd make an equation for creativity!" Chrome said, confused again.

"First: you steal human creativity and do matrix algebra on it, second: you don't!" Senku said, and grabbed some wires. "Lot here, I'll make fifty wires from left to right." Senku lay them on top of the bird. "And fifty more from top to bottom. See where they cross? The CPU can tell one how bright to be. The hard drive or memory will just give it a list of how bright the points should be."

"That's crazy- can it do colors too?" Chrome said, grinning.

"Yep! You change each number of how bright to three numbers. One is how red it is, one is how blue, and one is how green!"

"Huh?" Chrome scratched his head. "That'd make a weird image with no yellow or purple."

"Guess what makes purple?" Senku said, grinning.

"Makes? Uh, flowers and stuff?" Chrome said, and Senku sighed.

"I gotta explain colors. Color doesn't exist."

"Yes it does idiot. Your jacket is white, mine is dark blue or something, those are facts." Chrome said, furrowing his brow.

"Nah. Your shirt absorbs most of the light. Mine reflects most of the light. How much light is reflected controls how bright stuff is, cause our eyes see by detecting light." Senku said, pointing at their shirts.

"Well that makes sense, but that's just brightness, color is about the material." Chrome said. I did make plenty of sense that things were seen with reflected light, after all you couldn't see as well at night.

"Nah. Color is the wavelengths of light that are most likely to be reflected. White, black, and grey stuff reflect most colors equally, just they all vary at once. Red is longer light that oscillates slower, blue light oscillates quicker and is shorter."

Chrome scratched his head. "Light isn't all the same speed? And isn't it like an intangible thing, how could it be longer?"

"Well it is largely the same speed, 299,792,458 meters every single second, but it varies depending on weather its through water, air, nothing, or other common things." Chome looked impressed with how precise the figure Senku stated was. Senku drew some shapes on the ground.

"These are hypothetical light waves. The top one would be red, the bottom ones would be blue or maybe violet. The speed of oscillation is measured in hertz. One hertz means once per second. A light wave of one hertz would go from the start of a hump to the end once per second. Light people can see is much faster, red is about 430 terahertz, and blue is about 750 terahertz." Senku pointed to the top and bottom waves. "So if the wave hits your eye at the speed of light a red wave will go from top to bottom slower, and you eyes can measure how long it takes."

"Well that's crazy, and doesn't explain a ton of stuff! What even is a wave and how does light exist in the first place? You also never explained what long means! Or how many times every second a terahertz is!"

"A terahertz is a million million times per second." Chrome gasped, Senku continued. "Length is the distance between the tops of waves in length, not time. Visible light is 400 to 700 nanometers. A nanometer is a billionth of a meter."

"Wait do you mean there are invisible kinds of lights?" Chrome said, eyes wide.

"Yep. Ones that are faster or shorter are pretty deadly, they are, in order of increasing shortness, ultraviolet, which gives people cancer, but the atmosphere blocks it out, x-ray, which can go through people, meaning if you make an artificial eye that sees with it you can see people's bones without doing any, or uh, much, damage, and gamma rays, which kill you and go through stuff."

Chrome's jaw dropped again and he cackled. "Whoaa!! What prevents us from dying to gamma rays? Does the atmosphere also block them? I don't think that'd work cause they go through stuff, but who knows? Well, you do, right?"

"Yeh, I do know. The main thing that saves us is that they're rare. They can and have killed most things on earth when they're made near us." Senku said, shrugging, and happy no gamma-ray-bursts happened between the petrification and now, as living without land life would suck.

"Nothings protecting us... Are there science materials that could?" Chrome said, pale.

"Yeah, but we can't predict them coming for us without big telescopes and the materials wouldn't be great at protecting us without warning, and they're really rare, so don't worry." Senku said.

"Longer or slower wavelengths?"

Senku nodded, happy Chrome was catching on. "Terahertz waves can go through stuff but do it differently than x-rays and are safer, microwaves can hurt you by heating you up, which means they're great for cooking food, and radio waves make great communication mediums."

"Wait, can radio waves go way farther than visible light signals?" Chrome asked.

"No, but it's way easier and safer to make them super bright, and some can go around the world by bouncing."

"Cool, and you'd make an artificial eye like glasses to see it?"

"Yep. Those aren't hard to make at all, some rocks make electricity when hit by radio waves, which can go to an artificial mouth." Senku said.

"Whoa, neat. If that's how computers sent information instead of talking, how did they remember it?" Chrome asked.

"Before I answer that I'll tell you why you only need to use three lights to mimic any color." Senku said, and decided this was going to take long enough he'd better get started on the chemistry already, and grabbed all the stuff he'd need to electrocute.

"Oh right, I forgot!"

"Well it's really hard to measure the wavelength of light, and everything could get messed up, so eyes skip everything that's hard, and don't measure the wavelength of incoming light." Senku said, waving a high voltage cable around. "Eyes contain four sensors, one kind detect light in general, but it can't light apart, so we used it to see motion and at night, as well as to calibrate everything, so your eyes don't act weird. The other three each correspond to a kind of light. They don't actually have any clue what wavelength is used, but each is best at detecting either medium, so green, low, which is red, or high, so blue, wavelengths! They figure out that yellow is in between red and green, but tending toward green, so when red says 'there's something there', green says 'there's plenty there!' and blue says 'now I dunno about this whole "there's something there" idea guys', then the brain figures out there's yellow there. Now, the brain can only tell the difference between mixing colors and having colors in between in one case, when red and blue mix. That says to red and blue that there's green, but green sees nothing, so you know it's not a medium wavelength, and that's where purple comes from."

"Wait, so if your brain can't tell apart mixing red and green from yellow, then you could just use the three lights to fake colors!"

"Exactly." Senku said, and started making some more lethal chemicals. "Now on to computer memory. There have been a few ways of doing that, but there's one that is both doable not too far from now, and has a full spectrum from pathetic to the best technology can offer. It has many formats, the one computers used most in my time was hard disks."

"So how did these tough disks store information? It doesn't seem like you could make one out of switches."

Senku snickered. "It would seem that way, wouldn't it? Now I have a question for you, master science user, what happens when you use an electromagnet next to a magnetizable material?"

"Well metal gets pulled towards magnets weather they're electro or normal. Hmm, if it's past it's curie point then it becomes a magnet, actually it doesn't have to be that hot it's just gotta be enough electromagnetic force!"

"And if you reverse the electricity flow?" Senku asked, realizing they could make magnetic storage before they'd have anything fast enough to use it.

"Well, huh. Wait..." Chrome scratched his head.  "if electricity has a positive and negative, then the two of them swapping would swap what way the magnet your make is pointing!"

"Yep. What happens when a magnet and a coil of wire like in an electromagnet go past one another at super high speeds?"

Chrome scratched his head more. "This is a weird puzzle. You know the answer, and aren't telling me."

"Yes."

Chrome blinked profusely. "I'm going to blackmail you. I won't come up with guesses for this one, tell me or you don't get to talk science anymore." The truth way Chrome wanted to know and had no clue.

"I'll bless you with a hint, pitiful human!" Senku said, with a cackle, and electrocuted some stuff.

A second passed. "Where's the hint?"

"I just started doing it."

"Doing? You don't do hints, you tell people them!" Chrome protested.

"Well you do this hint. I'm done doing it." Senku dropped the wires on the ground.

"The wires... then- WAIT YOU MADE THAT ELECTRICITY BY MOVING COPPER PAST MAGNETS!" Chrome gasped, pointing at the generator.

"Yep. What happens when the magnets that make the electricity's poles are reversed?" Senku asked.

"I don't know, maybe it's like magnet-making backwards, the poles being reversed changes what way the electricity is going?"

"Totally. What happens when a long thing of magnetizable material is ran past an electromagnet? Imagine that when the computer has something to say it runs the yes or no answers that computers run on in as directions electricity can take through the electromagnet. When it's done it can go back to the start and move then now unpowered magnet past the magnets it made super fast, and it'll quickly go from electricity going in one direction, to the other, which can be detected." Senku said, and motioned manically, which was probably intended to serve as visual aid.

"That makes sense! How would you make something with enough magnet stuff though? Even if you made a pretty thin rope of iron, if that's possible, it could get tangled up, accessing thoughts would take forever, and it wouldn't fit in your pocket!" Chrome said, remembering how Senku apparently fit a computer is his pocket before the petrification.

"That was the first way people implemented the idea actually, they made thread of steel, which is like cleaner iron with extra carbon, and kept it on spools, which Yuzuriha can teach you about, and they weren't really ever used for computers. They had all the issues you thought of and more, but people found a use for them recording voices-"

"WHAT? You could capture the sounds people breathed out?!" Chrome gasped yet again.

"Yep." Senku was surprised this would shock Chrome. "The wire was terrible at recording voices though, and so people made tape or strips of metal and stuff coated in metal, that was the first of this that was used in computers. It was also good enough to record music-"

"MUSIC TOO? Your civilization captured voices in thread and songs in ribbons made of a miracle material you used mainly to kill each other, do you have any clue how crazy that is? You sound like a hubris tale in the 100 tales! As much as the idea of stealing voices is ripped right from the story of Speaker, I'm much more worried about the warnings the tales give! Like that one where the people need to win a war against those two villages and they make a thing called an ah-baulm that burns down a village with dark sorcery in an instant, and kill Hero-Chema and Naga City because the people of Hero-Chema and Naga City had burned down some harbor for war-canoes the slow way! Where magic and sorcery are paths to destruction, what guarantee do you have that, uh, the..." Chrome noticed how pale Senku was. "Uh, that the petrification wasn't like an ah-baulm of some-"

"CHROME DO YOU KNOW WHAT WORLD WAR TWO WAS?"

"No?"

"It was the war with the A-bomb, a weapon that disintegrated cities, which were pre-stone giant villagers with thousands or millions of people, the first and only two Atomic Bombs used in warfare were used on Hiroshima and Nagasaki, Japanese cities, after years of war." Senku tossed aside his highly toxic chemicals. "I'm meeting Ruri if it kills the chief."

"If it kills... Wait you can't kill villagers!" Chrome yelped. "Stay here Senku!"

"TSUKASA! GET OVER HERE!"

"TSUKASA! STOP SENKU, HE'S GONE MAD!"

A large oak behind the two rattled, aside from one branch. "Yes?" Tsukasa, trailed by three meter gouges in the grass when he halted himself after clearly accelerating quite a lot, had finished his deceleration by grabbing into the oak. He pulled his fingers out of the bark, with some effort. Homura swung down from the branch she landed on, which hadn't rattled due to her weight.

"Senku's gone mad and is going to kill the-" "They have purposeful tales about NUCLEAR WEAPONS!" "Stop him from being so crazy it's just a story about not being greedy for victory!" "These aren't random things the people who were resurrected didn't loose with their tech, this was on purpose! Maybe even planned!" "Senku's- you get the point! Crazy!"

"Chrome, I'll make sure he doesn't kill anyone. Senku, explain." Tsukasa nodded to Senku.

"You see this isn't anything accidental, we assumed these people were descended from people who got hit with some nitric acid, and lost their tech, it even made sense of the hundred tales including modern stories, but this is on purpose! It's a warning agaisnt nuclear weapons, it's 100 stories of warnings agaisnt gorillas that aren't on Japanese soil, lions, and nuclear waste and weapons. Chrome, in the story of the Atom bomb are there any bits about warnings?"

"If you find a monument to the people who died to Ah-Baulms, don't go near it if it has warnings? They're magic, the fire can last thousands of years."

"That's about nuclear waste, when you burn coal, it makes soot and smoke and ash, the ash in a nuclear weapon is a material that emits an invisible light, as well as chunks of itself moving almost as fast as light, you know how UV gives people cancer? It give people a little skin cancer, radiation give people every kind of cancer and often quite a bit." Senku explained to Chrome, then turned back to Tsukasa. "You know what this means, especially with the village being called 'Ishigami village', which got me thinking, that's my fathers name more than mine, and he was in space when the green light came."

"He was in space?" Tsukasa said, nodding with what was probably respect.

"What's space?" Chrome asked.

"Space is everything that isn't on earth, so earth is in space. Billions of suns and planets are in space too, but aside from them and other oddities, there's no air." Senku said, then continued. "He'd be the kinda guy to get a village named after him, though I'm dubious that this village has lasted thee thousand years."

"That's quite the leap." Tsukasa said.

"I don't plan on killing anyone, and oral histories are robust enough that Ruri could know multiple stories about three thousand years ago." Senku said, and pulled out some molten iron he'd apparently heated up at some point, and poured it into a sand mold.

"You still plan on barging in where we aren't allowed, don't you?"

"Yes." Senku said, and started walking to the bridge.

"You'll have quite a bit of trouble doing it without my help, but I won't stop you, if you don't actually plan on killing anyone."

"HYOGA!" Senku yelled.

"Yes?" Hyoga popped up from behind a tree in Senku's path.

"Have an iron spearhead, you're getting me to the far island."

"Thank you. Do you have a grip I could place around my spear?" Hyoga asked, untying the flint tip from his spear. "Preferably as lucubrated as possible."

"Hm, I'll grab something to make it slippery if you find a piece of bamboo that'd fit around it."

"Thank you again."

"Senku-" Tsukasa said, sighing.

Senku, Hyoga, and Taiju stood at the bridge.

"You still can't pass."

"Maybe listen to them, Kinro?" Ginro said.

"Hey! Can I join?" Yuzuriha said, and ran up.

"Sure!" Senku said. "Now out of our way."

"No." Kinro said. Hyoga flicked his spear, knocking Kinro's out of his hands, and shoved him to the side, catching his opponent's spear. Taiju merely picked up Ginro.

"Come on Yuzuriha, we've got stuff to learn!" Senku said, dragging her past so Kinro and Ginro could be let go.

Once they were on the bridge Hyoga threw back the spear. "Sound the alarm!" Kinro yelled.

"They're our friends! It's okay!" Ginro protested, but as always, rules were rules.

"Out of my way." Hyoga said to the short, pudgy man blocking their way, ringing the bell.

He yelped. "Magma!" And ran off.

"THE SORCERERS ARE BREAKING IN!" Magma yelled, and burst out of his hut. Senku wondered how he could tell in a hut and all, then saw Magma's surprised face. "I- Guess I was right! I'm always right!"

Hyoga glared at him. "Drop your axes."

"YOU DROP YOUR SPEAR!" Magma charged axes first.

Hyoga whipped his spear up at Magma's axes, knocking them out of balance, and, as magma closed into range himself, pulled on his spear like a level to turn it around and hold it in front of Magma's forehead already perfectly still, before Magma had a chance to block. Magma skidded to a stop but got slightly booped. "Dumb animal." Hyoga said.

"How dare you! I'll destroy you for- Ow!" The blood from the small cut dripped perfectly into both eyes.

"Taiju." Hyoga said, and began walking to the bridge to the far island with Senku and Yuzuriha.

Taiju stole Magma's weapons, took a rather devastating punch to the face in the process from a blinded enemy, laughed it off, and rejoined his party. Magma rubbed the blood from his eyes. He, obviously, stole Ginro' spear and yelled he kill them all. Ginro'd been cowed into coming along by his brother's nagging. Said brother was still standing guard, rules are rules after all, but this time on the near side of the bridge, able to fight as a spear used on a bridge is a powerful tool, especially when one had failed at their duty and had to send their brother along.

Blocking Hyoga, and by extension those other guys', path, was a man with confusingly colored hair. He was too old to be facing Hyoga, especially with this surprisingly frictionless grip and sharp blade. "Out of my way old man."

"You are as terrible as Magma's been saying! Tomorrow, we're killing ALL OF YOU!" The chief lunged forward, stepped back right as Hyoga stabbed, and knocked the spear aside with his club. "You see that! Just fight with less idiocy than Magma and you'll win-" Hyoga stabbed his shoulder, his spear whipped around again, and went for his eye, though he dodged. "CUT DOWN THE BRIDGE MAGMA!"

"OF COURSE!" Magma shouted back, and stood on the bride, facing to the posts that held them up. "I'll destroy them myself!"

"Magma!" Mantle shouted, realizing his "friend"'s plan. "Stay!"

"Never stray from a fight, Mantle! I'll kill them all just to prove I can!" Magma sliced through the ropes and planks under his feet, and grabbed onto the ropes as the bridge fell away from under him.

"Magma no!" Mantle shrieked, as Magma climbed up the falling bridge, and the planks fell from under the intended target.

Senku, Yuzuriha, and Taiju held onto the bridge for dear life, but Hyoga kept stabbing at a chief who had to stay in range to avoid Hyoga getting past the bridge and onto the island with his family. Eventually Hyoga plummeted due to this, and tucked his spear behind him to dive, though there were rocks under him surrounding him too well to get to the sea.

Chapter Text

Hyoga, now plummeting past Senku and pals, calmly said "Homura" and glanced down to see a rope being thrown from a crevice. He caught it, and swung to the left. Hyoga sighed, disappointed in himself that he'd be to far to kill Magma off, but he couldn't stop him from climbing the bridge/ladder unless he got to it or the top, and the top was preferable.

Senku was shaking, he wasn't strong enough to hold on for long, he was in no way stressed, but still, twig arms beats strength of heart in the real world. Taiju was stable, and climbing up, Yuzuriha was in a boat similar to Senku's, but her grip was stronger. Probably not enough to make up for her twig arms. Either they dealt Hyoga or Hyoga would deal with the chief, it was still a win-win, just, a cliff-side win-win. Magma roared. He was gaining on them, probably because Senku and Yuzuriha weren't climbing.

Hyoga greeted Homura, and undid the rope from where she'd tied it. "Good job. The girl I want is in the central building. Don't let anyone see from 'our' team either. Steal Gen's boat to cross."

"Understood."

Hyoga tied the rope to his old spearhead. He threw the makeshift grappling hook up to the post that once held the bridge. It was on. Hyoga had done so while the chief was looking away, so he threw himself up the rope before Magma could warn him. Magma and the Senku squad gasped as Hyoga reached the post. He swung around it and just as his feet touched the ground, he stabbed at the chief, who leapt back, getting cut on the thigh.

"What do you sorcerers want with us?"

"Ask one of the others." Hyoga said, calmly composing himself. "I, however, am attacking you." Hyoga stabbed directly into the Chief's heart, who survived only by sacrificing his club, which splintered on impact. "And I think I'm strong enough I deserve your full attention." Hyoga stabbed at his head, and, as expected, the Chief dodged, though his attention wasn't on Hyoga. That wasn't very proper.

"Jasper, you keep him occupied, I found his weakness." The chief sprung to his feet, and Jasper charged the spear-user from behind.

Hyoga's eyes widened, and he spun around, just in time to redirect two blades, far too long and smooth to be flint, obsidian maybe? The wielder had a beard darker than his hair, like the chief. He immediately tried to stab Hyoga's forward hand, and Hyoga was forced to lean into the strike, his assailant was far too close. Hyoga stabbed the knife-user's shoulder, shoving him back with extreme force, and getting away with a cut on his wrist. He spun around, noticing the chief throwing himself at Hyoga. Hyoga stabbed, right through the chief, who, recklessly, wasn't doing a thing to save himself. Instead, he grabbed the spear skewering his thigh, and snapped it easily.

Kokuyo, dripping almost as much blood as Jasper, grinned. He punched the sorcerer in the face. "Weak."

Hyoga flew back, now unarmed.

"Jasper, you'd better patch yourself up and check on Ruri." Chief Kokuyo charged the spear-user, and tackled him to prevent him from getting up. Evidentially, even if breaking noses was more satisfying, a fight-ending move was more practical. The boy struggled, but Kokuyo tied his hands together and threw him off the side off the island, before stumbling to the ground, groaning. Magma climbed up, and cackled.

"Those sorcerers fled like wimps! We'll be able to take them all! I'll go swim over and get Kaseki to fix the bridge, then we kill them all!"

"For once, you're saying sensible things Magma." The chief said, and poked at his wound.

"CHIEF!" Jasper yelled. "They took her!"

Chapter Text

Senku swam like his life depended on it. Technically speaking, it did, because if he were loud enough to get Taiju to notice him, then he also be loud enough for Magma to spot him and chuck a rock his way. As he got to the edge of the island closest to shore he pulled himself away from where he'd be visible to the villagers, and panted. Senku noticed Taiju and Yuzuriha getting farther from him. Having caught his breath, he went to catch up, but saw a gap in the stone cliffs. Peering in he saw light at the other end, and concluded that he'd found a shortcut. Senku swam quickly by his standards, but recognized that he was relying on a crutch in the shortcut. Like his father, he'd fail a clothed swimming test. Unlike his father, he lacked a work ethic or an amazing kid obviously destined for greatness. Whatever. He'd make it this time. If the spaceship he'd eventually slap together in this stone world crashed, he get to shore. If his muscles failed him, he'd do better. Senku pulled off his bag, and went to fill it with acid and wood ash to inflate it, a makeshift lifesaver if you will, when he ran face first into something. This time it wasn't a moderately lit rock though, but a raft. A well made, village style, raft, with two bodies in it. One was blond like Kohaku, and resembled a pop star, just in cavewomen cosplay, and was tied up. The other was a bloody mess with the face of Hyoga. Senku wondered how Hyoga could have lost and weather he'd survived, as the quiet was interrupted by Senku's breathing, dripping around them, and clacking. Then the blonde girl turned, hearing Senku's breathing somehow, and bloody one coughed weakly. They were alive then.Senku hummed and whispered, going to untie the girl. "Wonder how she heard me, maybe she's got ears like Kohaku's eyes-"

"She didn't hear you, she heard me." Homura said softly and pulled a knife to Senku's throat. "You can live if you'll give Hyoga the antibiotics you're making, and won't tell the others how this happened. Not only would it give all of this away, but they'd figure out about Gen and Minami being in the village on your orders, and that'd get them lynched, and ruin everyone's trust in you and Tsukasa."

"No one told me you were secretly a spy, diplomat, assassin, and boat rower all at once! Terms accepted."

"That was surprisingly easy."

"It really was."

"Oh, and don't tell Hyoga I let you live. He told me to kill anyone who learned the plan."

Senku nodded. "Not a killer then?"

"Not yet. I would kill though, just knew the only way to save his life was with yours." she said, nodding to Hyoga's bloody body.

"So pragmatic, not mindlessly cruel, good."

"Few are."

'Hyoga is.' Senku thought. "I suppose." Senku was released, and climbed into the boat, waiting to leave.

"What're you in there for?"

"Leaving."

"No we're not." Homura said, and sat down. "Night time launches only. Otherwise we'd get caught."

"It'd love to fashion a stirling engine for this so it'd be quieter or something, at least anything productive, but I don't have my tools." Senku groaned. "What's in there?" Senku pointed to a basket in the corner of the cave.

"Spare resin and waterproofing stuff. Oh and some wine and preserved foods for when Gen needs to bribe people to leave him alone long enough to get to the boat before everyone's up and would see him. Water's the only bit of it that's fresh though."

"Is there any meat?"

"Yeah?"

"With bones?"

"Yeah?"

"Uncooked?"

"Unsure."

"In tubes of intestine?"

"I think?"

"Water's clean and potable right?"

"Taste's great and it's clear."

"Cool. I'll be productive by stitching up Mr. I-Have-a-Spear-and-am-Therefore-Invincible's wounds." Senku checked for bones, found some uncooked bird one's, began fashioning a needle, and asked for Homura's knife to slice thread from the animal gut.

"This seems unsafe. Sure we shouldn't wait for antibiotics?"

"I mean soap's a terrible antiseptic, but if they've got water I can clean all of this up a little."

"Don't get him killed."

"Untie her, I have to talk to her." Senku tossed the knife.

"...okay."

"She's sick anyways, tying up sick people is like, double mean."

"Ruri is it?"

"LET ME GO-" Homura stuffed a rope she was winding up to put away in the girl's mouth so she wouldn't give them away.

"Stay still please. I'm Homura here would probably kill the both of us if we presented a threat to the man I'm stitching up." Senku pulled taught his catgut thread's knot, and peered at the large cut in Hyoga's side. "And noise is a threat I suppose. My name's Senku by the way."

Ruri gasped as her captor removed the rope from her mouth. "Really?!"

"Quiet." Homura whispered and went back to organizing the rope.

"You're Senku?" Ruri coughed briefly, a dry and painful one. "Do you have another name?"

"Am I someone else? No."

"No, like, a family name, one that goes before Senku."

"Yep! I was gonna ask about that. My family name is Ishigami. Do you know the namesake of the village?"

"His name was Byakuya."

"Well, my old man's dead then I'd suppose."

"Thousands of seasons ago, he passed on, I'm sure. He's buried nearby. He instructed the first priestesses to tell you the final story of the hundred tales when statues spoke, so I'll ask, do they, and do you wish to hear."

"Burred nearby... interesting. Of course I want to hear! And yes, we do speak. I'm a statue of course! Not a sorcerer." Senku cackled softly, then grimaced. "Homura, get something that I can make a Thomas traction splint from. His femur... It's more urgent than these cuts."

"Got it."  Homura hopped off the boat and out of sight. Senku hopped she'd get good materials.

"So the statues do wake up." "While I know what a scientist is, it's still vary sorcerous of you to assume you can fix a broken thigh. His bone isn't just broken, it split down the middle. It's swelling, from the inside of the bone leaking. He's not going to make it past even me."

"I can totally save him." Senku quipped. "I'm shocked that you know why edema and hematoma are common is tissues surrounding broken bones, and Homura knows what a Thomas splint is, but that's the point. We can find out what causes people to die, and prevent that. If you can't fight what you don't know, then, well, the inverse of that is that you can fight what you do know."

"You seem confident. How do you stop the blood fever?"

"Blood fever?"

"Happens when you get cut like him. Magma's father fought a lion and beat it. When my mother gave birth to Kohaku she was a bloody mess, but wasn't dead. Soon enough, they were dead."

"Yeah. Bacterial infection was one of the last that we figured out." Senku grinned. "It's actually the same thing you've got. Some sort of infection. Probably not viral. Not sure though, if you have a viral infection, you're dead as nails. If it's bacterial like I think, well, I don't think his blood fever will take him out. There's two ways to beat bacteria. Number one is to not let them in." Senku scrubbed his bar of soap to wash out Hyoga's cuts. "This is soap. It's made of the same stuff as bacteria's skin, and as such will merge with the skin to rip the bacteria apart. You can pull a similar trick with alcohol, but not like wine, pure alcohol. We have some across the bridge. This is why you clean your cuts. If you also wash you hands, bathe, and brush your teeth, you'll prevent most of whatever you've got, but you started bathing too late I'm sure. Not to say it's terrible and pointless, you don't want any more infections, and some fevers are helped by warm water, but it's not the main purpose. Once you have a bacteria, you need to kill it. This is really hard. It's literally trying to kill a thousand million bugs that breed like rabbits in a pile of even more friendly bugs, that's how bodies work, and it's easy to die trying on this front. Antibiotics and bacteriophages can be used to treat wounds of the sick, they are compounds or structures that only kill bacteria. They do usually kill friendly bacteria, but your body has more of that then unfriendly stuff, and will shelter the friendly stuff somewhat, so you won't be adversely affected much unless you take huge doses, so we can go make some sulfa when we get to my side of the bridge, that's a kind of antibiotics."

"Scientists really are like pre-stone priestesses, you sound like me. Now, do you want to hear your story or not?"

"Yeah. I'm dying to know how that old man founded a civilization that lasted thousand of years and forgot to make them remember what bacteria were. Bacteria are everywhere! Functional Nukes, sorry, Ah-Bauhms, aren't ANYWHERE WITHIN TEN THOUSAND KILOMETERS!" Senku sighed and Homura whacked him with the stick she'd found for a splint, appearing as if from thin air.

"Quiet."

"Sorry. Good stick, though it's only one..."

"Tension splints only have one right?"

"Modern ones, older designs used two. It'll do. Still surprised you know what one is."

"Me and Hyoga both work in very dangerous fields. I can get another much faster."

"Do it then, while I finish washing out these cuts and Ruri here gets a turn to speak for once."

Ruri sighed. "So, the story of Senku? Tale 100?"

"It's named after me, wow. Let's have it."

"Mecha Senku here! This isn't a science this time, just a quick note. Please read the manga or watch the show, this story will not be here. If you can't see the show (the best way to see Senku's exploits) for whatever reason, here's a link to that part of the manga, use an adblocker, just cause this is legal doesn't mean it's safe! If you have a copy or have the money lying around, be sure to get the official release, it'll be a better experience, support the writers, and be less sus. If you like canon, you'll know the story already, enjoy! My ordinary science job was stolen by A/N today, so see the lower notes for fun me-style clarifications!"

"Back in the hundreds of millions of seconds, my old man was on an island and making stories. How nostalgic, it's just like him." Senku sighed. "Well, it's night now. You said that his actual grave is there?" Senku pointed across the water.

"Deep in the forest. I'd take you, but I'm in no shape." Ruri wiped blood from her lips. Her ability to talk without heavy breathing had gone toward the end, and dragged it on until she was a coughing mess.

"Got it. We'll patch you and him up real quick, don't worry. You'll be on your feet again in a week, and him in a month or three. That broken rib surprise was a real downer."

"If he makes it past the blood fever."

"He will. If he dies it'll be from some silly internal organ failing." Senku waved over Homura. "I'm weak, be a kind manly tiny girl and help me get this silly injury victim into the boat." 

"Alright."

Senku peered up as they climbed. He and Homura were lugging the the poor bastard who'd fallen off a cliff, and Ruri was coughing her way up the slope to the Kingdom- err, Democracy of Science. Kingdom sounded better.

"Senku, Tsukasa is semi-fighting 8 people." Homura whispered.

"What??" Senku peered over the grass. Tsukasa was preventing every fighter in the village from crossing, Kaseki, Chrome, and Kohaku were halfheartedly threatening him from the other side. The only people really attacking him were Kinro and Ginro. "Well fuck. We'd best stop them. Homura, go tell everyone you have a hostage, and play along when I reveal myself."

"Okay..." Homura grabbed Ruri by the shoulders, tied her hands together, and dragged her out. "I have a hostage!"

"RURI!" The chief exclaimed.

"I'll kill that bitch." Kohaku whispered.

"Yeah, I have a hostage too." Senku walked up, dragging Hyoga. "Now what do you hope to accomplish?"

"Hyoga!" Homura said, quite convincingly. "I was going to make you help him. Why are you behind me?"

"Long story." Senku said. Dam she was a good improvisor. "You know your bandages well, but without this splint he'd have died. I also know that he's definitely infected with something. He won't outlive Ruri."

"Well I can make him outlive her." Homura held a knife to Ruri's throat and the villager gasped.

"Or I can save them both." Senku shrugged, and casually placed the needle he'd used to stitch up his "hostage" to his neck, brushing his thickest veins.

"With what? Antibiotics?"

Homura was a hell of an actor. Senku grinned "Yeah. I can make a dose in about 48 hours, and with infections like their's it'll take a few doses, but I can just do it. I will, however, need you to allow yourself to be punished however the villagers demand, you did kidnap her after all." Tsukasa sighed softly, exasperated. Senku gave him a knowing glance and chuckled.

"For the ancient cure that ended disease in the old world, okay." Homura dropped Ruri, who fell into a coughing fit.

Chrome stopped glaring at Homura, and looked quizzical. Senku had explained antibiotics as only stopping bacteria. Ruri, and he supposed Hyoga, had bacteria, but other sicknesses existed. Chrome went back to glaring, but at Senku this time.

The chief rushed past Tsukasa, who let him through, to hold Ruri. "Ruri!! She needs rest, and your kind need to leave." He glared at Hyoga, then Homura, the realized that they were the main ones who'd wrong him and his daughter. Hyoga was a bloody mess, and Homura was at his mercy if he allowed the quack to practice the medicine the girl was strangely trusting in on her man. Women. He wondered though, she had to be skilled, how could she be both skilled and so mentally weak as to fall for sorcery?

"Deal says I gotta make antibiotics though. Can't make them on the move. I'll leave after Hyoga recovers. And Ruri, If you'll let me." Senku nodded to Homura, who was tending to Hyoga.

"You can treat her if the spear-basterd survives until the tournament to find her a husband!" The chief laughed as it that were impossible.

"Shake on it?"

"Huh?!"

"It means-"

"I know what a handshake is!" Kokuyo yelled. "Just slightly shocked you'd bet on it. If you fail you leave." Senku nodded and the shook on it.

"Alright guys!" Time to make some sulfa! We've got enough wine but we'll need *much* more to make more than one dose.

"I can steal more but the good stuff is going to whoever wins the tournament." Gen shrugged.

"WAIT IS NO ONE GOING TO TALK ABOUT WHAT HAPPENED?" Chrome screeched.

"What?" Senku said, stretching.

"You plotted with her, which makes you a like crime assistant in kidnapping Ruri!"

"So? We're getting Ruri medicine cause I could stage a hostage negotiation."

"And your murdery story intentions?"

"I had a very good conversation with Ruri." Senku grabbed his patient as Magma dragged off Homura. "Now do you want to do science or not Chrome?"

Chrome took a breath. "Well we've got to do science to save Ruri I suppose."

"Yes, we do."

"You have given me a hell of a task." Tsukasa said, watching Senku mix his concoctions.

"I haven't made you do anything."

"Implicitly." Tsukasa sat down. "I've had to talk them down from killing her to 'just waterboarding her a little' to keeping her in a cage until she's behaving better."

"You could've let her die."

"Senku. You know something? You would let her die. There were at least three ways to leverage her death for a greatly increased benefits. What is she?"

Senku sighed. "Three things. First is for you. You'd prefer it if the villagers join peacefully and not just as a place, but as a people. Giving them 'control' over her helps a ton. Second, she's horrifically qualified. Her utility value is unprecedented." Senku turned back to his work.

"The third?"

"I don't actually kill if I can help it. I'm not sure why everyone with a lot of charisma thinks I'm a monster. I think all of our kind can just see how willing I am to employ death. I would. But push had better come to a specific shove."

"You're more principled than I'd hoped."

"You want something." Senku grinned. "What?"

"What's needed to mass produce the revival chemical?"

"A catalyst. Think palladium would work but the nearest deposit is in China. Platinum isn't a bad idea though, if we can find any literally panning for gold at random and hoping."

"Then next question, how could we skip fossil fuels and go to a renewables-based economy?"

"We can't. Steam power is a stop we can't overshoot, and internal combustion engines will be the only vehicle-mobile power sources, and we may have to go to South America in the near future."

"Then what do we need to use electric motors." Tsukasa sighed.

"We don't necessarily need to to be eco-friendly." Senku grinned. "Biofuels are nearly carbon neutral the carbon in them comes from the air after all, and anyways the ecology can take even a few million people using coal, let alone high efficiency diesel and petrol engines, to do all sorts of stuff. Global warming needs huge output, which was only achieved in the past by having billions industrialize with coal at once. So we just need a safety net that'll allow the billions we'll eventually resurrect to industrialize with biofuels, hydropower, and solar."

"Solar. what's that need?"

"Semiconductors. Isn't a viable option until we're almost ready to get everyone out of the statues."

"Well. I support the biofuels thing. What do we need to start making tons of them?" Tsukasa asked.

"Uh, I'd hope for corn, but sadly that's not an option. If we want to go with cellulose options we need a lot of vinegar, significantly more trees, and a giant tank we can heat up. And fuel to heat it. So fresh trees to ferment and dead trees to burn I suppose."

"Got it. Thanks." Tsukasa stood up, stretched, and snatched his weapon up.

Hyoga's fever peaked at about 38 and a third degrees, (101 F) and it started to lower after that. With one day until the tournament Ruri was in her room when she collapsed and the chief allowed her to take the antibiotics.

"It's Pneumonia." Senku grinned. "We win! She'll be better in a week or so, just gotta give her a few more doses."

"I don't like this." The chief said.

"I do!" Chrome said, and helped Ruri to a chair. "I said I'd find a cure."

"What're the laws about joining the tournament?" Senku asked.

"They were that you had to be of age, but we've amended it to outlaw anyone who cannot marry the priestess-" Kohaku gasped. "and who cannot trace their ancestry back to the village within two generations."

"Dam. Chrome, you'd better hope that Kinro winds up in the same bracket as Magma, none of us can help. Well. I can."

"No sorcerous cheating!" The chief grumbled.

"My father was a villager. He's dead though."

"There's no way to confirm that then, and I thought you were a thousand year old statue?"

Senku grinned. "Ask Ruri."

The chief paled. "Well, she'll decide then." Kokuyo walked away, grumbling about how he hope sorcerers were really scrawny and not hiding muscles.

Chapter Text

The brackets came in, and Chrome was going to fight Magma before Kinro. Ginro would fight Magma first, then Chrome, then Kinro, assuming any matches before were won. "Fuckfuckfuck-" Chrome shook his head. The first fight was Senku and Magma. Chrome was in the same bracket as them. And Kinro was on the other side. Chrome sighed, he hadn't had the time to train much, not at all. "Senku, is there any scientific way to make me win?"

"Well, not really, we haven't got time to use any of my favorite cheating methods. I do think, however, that I've got some caffeine, and I know a very cool trick." Senku chuckled. "It's time to reinvent modern medicine!"

"Senku we have like 20 minutes!"

"Yes." Senku nodded calmly. then grabbed a small piece of metal. "Thankfully I made this ahead of time!"

"That is?"

"A hypodermic needle! I have type AB so I'm useless for tests."

"Type?" Chrome asked.

"Of blood. GEN!"

Gen peaked around the corner. "What's going on, Senku-chan? I heard something about blood."

"What's your blood type?"

"Oh, I didn't know you cared about that sort of thing, pegged you as an almost, uh, anti-superstition person." Gen smiled innocently. "B."

Senku stabbed Gen.

"OW! What's that for-ohhh."

Senku drew the blood, and it filled a tiny vial attached to the needle. Senku then heated the bronze needle til the glass could be clamped off, incidentally sterilizing the needle. "You know your RH-factor?"

"No? What's that?"

"Sorry, I meant positive or negative."

"Don't know."

"Dam." Senku sighed. "We'll just go with 'RH:Chrome or RH:Anti-Chrome.'" Senku stabbed Chrome. He stuck the bloods together, and looked at them for a bit. "Yuzuriha! Taiju! You two are being a bunch of bores, get over here and give me your blood!"

"Senku, what are you doing now?" Yuzuriha sighed.

"Reinventing blood typing." He stabbed the two of them. "Yuzuriha's O-type so it doesn't matter what she compares with, but she's a universal donor. Either Chrome's blood will bond with Taiju's, making him AB type, or won't, making him A."

"I still don't understand any of this." Chrome said.

"It's organic chemistry, no one understands it." Senku shrugged. "We just sorta see what happens and weather it was a pattern."

"That was a joke, right?"

"More or less."

"Senku, did someone loose a lot of blood?" Yuzuriha asked.

"SOMEONE'S HURT? TAKE MY BLOOD!" Taiju gasped.

"Taiju, there's a like 75% chance your blood could kill someone. Anyways Chrome's fine, we're just gonna engage in some good old fashioned cheating."

"Am I going to have to eat someone's blood for power? Science really is like a hubris story." Chrome mumbled.

"Nah, I'm gonna inject it into you." Senku looked at his vials. "Chrome is A type, and his Rh-positivity is the same as Taiju. Sadly Yuzuriha isn't a universal donor, because she's's got RH-not-Chrome."

"What happens if you inject me with RH-not-chome?"

"Nothing really. Just the second time we do it you die a horrible death."

"Are you sure this is safe."

"Not at all." Senku started pulling much more blood out of Taiju, and didn't seal the vial.

"Is Taiju gonna survive without his blood?" Chrome asked.

"He'll be fine. He's done this before."

"I have?" Taiju asked.

"Blood donating." Yuzuriha said with a sigh.

"Oh yeah we've all donated blood!"

"Donated implies people need the blood. Why would you need extra blood?" Chrome asked.

"Hyoga needed blood, right? We're both AB, so we matched and I just used my blood instead of wasting the rest of your times."

"Ohhh, so like, that helps people get better."

"Yep." Senku chirped.

"But- I am better."

"You're not best though!" Senku exclaimed. "Blood takes oxygen, which has the power to release the chemical energy in food, and gives it to all your cells. If you have oxygen and food in your cells you can do stuff. Fighting uses a lot of energy, sometimes faster than a normal amount of blood can carry, and having more blood means your energy regenerates faster."

"So I'll attack like crazy fast and not get tired?"

"Yeah, more or less." Senku sterilized the needle for the umpteenth time and injected Chrome. "Eat this. It has caffeine. That's a drug that'll make you excited and less likely to hold back. It'll also make your body a little better at keeping your cells full of the other half of the energy equation: food."

"Shouldn't I just make sure I have enough food in me?"

"Theoretically yes, but eating before exerting yourself is risky, however sugar can be extracted from plants, and a little isn't going to cause indigestion unless someone mixes in other stuff like longer carbs. If I mix the little I have left from when Tsukasa prevented me from making weapons with some salt and water, we can make Gatorade!"

"Help from alligators? Huh?"

Senku laughed. "No, it's just a drink athletes used to like, it keeps you fueled up and hydrated!"

"So I won't get too thirsty or hungry!"

"Yep. Now go!" Senku shoved Chrome. "Hopefully the blood helps and doesn't kill you." He mumbled.

"I thought we matched?"

"I could be wrong. Now win!"

"Got it!" Chrome ran off.

Chrome marched up to the arena. Senku was calmly sitting there with his legs crossed, weaving something. "The hell are you doing here?"

"Ruri confirmed my father was a villager." Senku stretched. "I'm competing!"

"That's fully impossible."

Senku chuckled. "You'd think, but this village is as old as the statues, and coincidentally, my father wasn't dead when that happened, so there was an overlap."

"You're nonsensical. And anyways what can you do? You didn't bring a weapon."

Senku smiled. "No one got around to outlawing sorcery."

"I wish I had more time, and a more tired Magma to fight, but I'd love to see the damage I can do." Senku tapped his foot nervously.

"Senku?" Chrome sighed. "You're delirious."

"Nah, let's-"

"LET'S WHAT LITTLE MAN?" Magma grabbed Senku by his shirt and pulled him to his feet.

Magma went to drag him into the ring. "Hey, gimme a minute."

"Huh?"

"No rule on who gets to start it, and I want a minute to finish this." Senku held out his woven fabric.

"I'll tear it up when we start then. Sorcerers are so strange and womanly." Magma dropped Senku and went to grab his axes, thankfully replaced with blunt clothed ones for the the tournament, to practice.

"Senku, you're insane, what can some fabric do against Magma? Maybe run a bit to tire him out then forfeit?"

"Not a bad plan. However, this isn't a weapon." Senku grabbed a cloth-tipped spear and walked into the ring. "Ready!"

"It's been about a minute, you're not a punk who'll keep me waiting. Good on you. Now time to break some bones!"

"START!" The ref shouted.

Magma lunged at Senku, who ran away, circling around until the wind pushed his hair away from his eyes rather than into them.

Magma followed and cackled. "The weak should learn from rabbits! Being downwind keeps you hidden, and I can face you unbothered, but you must flee to keep your hair from your face!"

"Yeah but it keeps me safe." Senku poured jars onto the ground. A foul-smelling gas emerged and flowed to meet Magma.

"AHHHHG-" Magma face away and rubbed his eyes. "IT HURTS! CHEATER!" Eyes closed and red, he lunged at Senku, who dodged around him. Magma fallowed on sound alone.

"You have five senses, Magma." Senku put wax in his ears. "I can take away three."

"I'LL KILL YOU!"

Senku pulled the stomach of an animal out of his cloak. It was small, but stretched by whatever exceedingly light filling it contained. He dodged another attack, and threw it towards Magma. It floated up every so slightly, and right when it neared his head Senku threw a small glass jar with copper spikes sticking out into it. It exploded brilliantly, and Magma's head snapped the other way and he fell to the ground. Senku took the opportunity to pour more of the gas on him. Blood trickled from Magma's ear as he stood. He opened one eye and screamed.

"YOU DEMON! I'LL KILL YOU ALL!" He kept the eye slightly open despite the pain it must have caused, and, coughing from the gas he inhaled, punched Senku right out of the ring.

"Senku is down! And knocked out!" The ref waved his hands. "Magma wins!"

Senku groaned, and purple bloomed on his face.

"NOW WHAT THE FUCK WAS THAT?" Chrome slapped Senku repeatedly, on his forth attempt Senku's eyes fluttered.

"Fuck that hurts..."

"EXPLAIN?"

"After I die in peace." Senku closed his eyes.

Chrome slapped him. "EXPLAIN?"

"Owww- okay, I will. Mustard gas is just sodium hydroxide and ammonia. Hydrogen-oxygen mixtures make great flashbangs and can be made with water and electricity. Now. Sleep time." Senku went to sleep.