Get excited for these character tropes from Dr. Stone.
Kingdom of Science
Pre-Stone World Characters
In the year 2019, Earth's entire human (and sparrow) population were petrified into stone statues under mysterious circumstances.
Roughly 3,700 years later, a number of people either broke free from their petrification through sheer willpower, or were revived using Senku's de-petrification formula. These people would go on to join Senku in his quest to rebuild modern civilization.
- And I Must Scream: As Senku noted, it is possible to remain fully conscious while petrified by keeping your mind really busy at all times. While this comes at the cost of unimaginable boredom, it's perhaps better than the alternative; quickly losing consciousness and the ability to break out on your own.
- Charles Atlas Superpower: A large chunk of the characters have one area of expertise that they're almost superhumanly skilled at. For instance, Senku is a genius among geniuses, while Taiju is an indefatiguable Stone Wall.
- Fighter, Mage, Thief: Senku (who is referred to as a "sorcerer gentleman") thinks about this trope after he first de-petrified by acknowledging that there's a limit to what his knowledge can achieve without Taiju's great strength or Yuzuriha's super dexterity.
- Good Scars, Evil Scars: The crack marks on Senku, Yuzuriha, and Taiju are small and neat, in contrast with the very large cracks that often span across the faces of Tsukasa and his goons from his Empire of Might. Hyoga, the most evil of them all, has the most extensive scarring seen on a revived character. Meanwhile, the ambiguously neutral Gen has a single, moderately sized scar.
- Healing Factor: When going through the depetrification process, no matter how small the petrified body part is, all injuries are miraculously healed, including fatal injuries. Even braindead patients will wake up, fully conscious, when they are de-petrified.
- Improbable Age: Despite all being teenagers, most of them are extremely well-versed in at least one area of expertise or have some special skill (or several, in Senku's case) that would realistically just take several more years to master than any of them have actually lived. Senku himself, of course, is the main offender; he's probably several times more knowledgeable than any doctor or scholar could ever hope to be.
- Really 700 Years Old: All of these characters are really thousands of years old, as they all were frozen for over 3,700 years before being freed. Of particular note though is Senku and Taiju, who were actually conscious the entire time and are therefore technically really, really old men still living in their teenage bodies (though they evidently still act just like they always have upon being freed).
- Scars Are Forever: Those who are revived have prominent "cracks" on their bodies where the stone broke apart unevenly, as a result of thousands of years of weathering damaging the stone and causing the surface layer to flake off like dead skin. This creates quick identifiers to separate those who were de-petrified and those who were born into the Stone World (Though female characters' marks tend not to be on their faces). During the Treasure Island arc, several characters including Taiju are petrified a second time; when they're restored a few days later, the stone transforms back into flesh rather than flaking off, which also heals their previously-obtained scars.After Tsukasa's second petrification and subsequent revival, Senku is the only member of the Perseus crew to keep his scars. The rest of the crew replicate their old scars using paint as a display of unity, promising to remove them together once the threat of petrification has ended.
- Taken for Granite: All of these characters were frozen in stone for thousands of years before being freed, whether by their own determination or through Senku's de-petrification formula. Interestingly, it seems that it's possible for people to remain conscious and eventually break free from the stone by themselves as long as they keep their minds busy (as demonstrated by Senku and Taiju); otherwise, consciousness is quickly lost and the person will have to be freed by someone else. They will also wake up completely unaware of their circumstances (as demonstrated by everyone else).
Voiced by: Yuusuke Kobayashi (teen), Mikako Komatsu (child) (Japanese), Aaron Dismuke (teen), Mikaela Krantz (child) (English), Alejandro Orozco (Latin American Spanish)
- Accidental Marriage: Because Chrome passes out from the injuries he sustained fighting Magma, Senku (who was planning on throwing his match to Chrome) ends up winning the village games and marrying Ruri. However, thankfully, he also became the village chief as a result of his victory... giving him the right to divorce Ruri on the spot not 5 minutes after "marrying" her. Ruri, naturally, was dumbfounded by the whole thing.
- And I Must Scream: Unlike many others whose consciousness faded over time after being frozen, Senku stayed awake during his entire petrification by counting the seconds starting the moment he was frozen. However, he ends up just fine after waking up.
- Anime Hair: Bigger than his head even. It's especially noticeable, since Dr. Stone trends more towards reasonable hair styles than some animes. Also, it has the tips dyed.
- Attractive Bent-Gender: When the gang tries to create suitable candidates to infiltrate the Head's harem of girls, Senku turns out to look surprisingly not-too-bad while disguised as a girl. Unfortunately for the sake of the mission though, his voice is too deep to be convincing.
- Back from the Dead: Tsukasa actually killed Senku in chapter 10 but he was able to come back to life due to the unpetrification process healing the bodies of the petrified.
- Beyond the Impossible: Not only did Senku count off the seconds for thousands of years while frozen, but was also actively thinking to himself about the situation at the same time. To get an idea of how ridiculously difficult this is, just try thinking about anything constantly for 5 minutes while also actively counting. To do that for thousands of years is some insane multi-tasking. For comparison, Taiju, who also remained conscious, had no idea and could only obsessively think about his love confession.
- Born Unlucky: Whenever a situation comes down to pure luck, Senku always gets screwed, leaving him to use skill and effort to turn things around. During the Village Games, the group ended up drawing the absolute worst tournament bracket possible, and at the climax of the second arc his attempts to quickly create gunpowder are thwarted when the bat guano fails to react with the nitric acid, prompting Gen to quip that "your luck has always been crappy, hasn't it?"
- Often uses the number ten billion, for example by claiming something is 10,000,000,000% certain.
- "Not one millimeter" comes up as the negative of the above, for example "That speech did not move me one millimeter."
- "This is exhilarating", "Get excited!" and variants is also used a lot whenever he either succeeds in his goals or a new challenge that needs science comes up.
- To a lesser extent, he's fond of saying "All of America weeps" when he's discussing matters supposedly linked to the country, like automobiles or firearms.
- Celibate Hero: He's a combination of the "thinks love is a distraction" and the "socially awkward" variety. When Kohaku tells him that she's "starting to fall for him" when he first meets her, his reaction is to frown and sweat nervously before getting annoyed and quipping that "a brain in love is the most illogical variety of trouble" (Luckily for him, she didn't mean it that way, anyway). Amaryllis's great beauty and charm also have no effect on him, shocking her and leaving him totally unimpressed. A few characters, such as Gen, believe that Senku is simply laser-focused on restoring the world and might be more open to pursuing romance once he's accomplished that goal, but Senku himself has neither confirmed nor denied this idea.
- Clean Dub Name: The Brazilian Portuguese dub managed to pronounce his name in various different ways rather than "senkoo". This is because his name name sounds like "sem cu" ("without an ass(hole)" in Portuguese).
- Character Tics:
- Early on in the story he tends to put a hand on his neck and roll his head in order to crack his neck joints. After Tsukasa "kills" him by breaking his neck, Taiju and Yuzuriha figure out that he was doing this gesture (which he never did in all the time they'd known him) on purpose — to get Tsukasa to attack a place on his body that was still petrified.
- Later on he tends to pick in his ear with his pinky finger, usually to show annoyance or nonchalance towards someone.
- Whenever he is in the process of performing mental calculations, hell raise one hand up, with the first two fingers extended, in front of his eye.
- Chekhov's Skill: At the beginning of the series, Senku's skill at counting the seconds, up until his revival, is mainly used to establish how he knows how long everyone's been petrified for. However, during the battle against Ibara, its his three-thousand-plus years of practice at counting seconds that allows Senku to perfectly time his moves against the set speed of the Medusa-device's petrification ray, enabling him to ultimately outsmart Ibara.
- Childhood Friends: Formed a Two Guys and a Girl trio with Taiju and Yuzuriha up until high school. Interestingly, both he and Tsukasa believe that the four of them would've been great friends had they met Tsukasa during their childhood, with Senku imagining a What If? scenario where Tsukasa would have protected him and Taiju from bullies.
- Child Prodigy: One chapter shows him reading a book about electromagnetic forces in class while the teacher is explaining basic addition.
- Combat Pragmatist: Since he's got pathetic physical strength and no talent for fighting at all, he's not above hitting below the belt as a last resort means of defending himself. Just ask Ginro.
- Creepy Good: Whenever Senku's plans work out, he puts on a Nightmare Face and talks to himself. This, combined with his red eyes, makes him look just like a villain. Despite this, he's a good guy through and through, who wants nothing more than to restore humanity. This is often Lampshaded by Kohaku.
- Deadpan Snarker: Fitting his intelligence, Senku is very quick-witted and has a dry sense of humor; about 90% of his dialogue consists of teasing or playfully insulting his friends in one way or another. Despite this, however, he is capable of being genuinely friendly... when he feels like it, and unlike many hyper-intelligent genius characters in fiction, he doesn't actually look down on people who don't match his level of intelligence, being able to find usefulness in most people.
- Defeat Means Friendship: Although a common Shounen trope, the amount of times Senku has caused this is staggering, considering he doesn't quite fit the typical Shounen protagonist mold (being an Insufferable Genius and Jerk with a Heart of Gold) and the fact that his enemy's defeats are caused through guile, cunning, science, and trusting his allies to carry out vital tasks, rather than straight-up fights.
- Determinator: Despite his lack of physical strength and durability, Senku has tremendous mental fortitude; he was fully conscious for the entire 3,719 years that he was petrified, and he spent the entire time counting the seconds in order to keep track of time. Even more impressive, he managed to retain his sanity despite the unbelievable boredom that must have ensued.
- Disappeared Dad:
- As his dad Byakuya was up in space during the stone explosion (and also eventually founded the village Senku now controls), he's long dead by the time Senku is freed from his petrification.
- Furthermore, with the reveal that Byakuya was only Senku's adoptive father, the status of his biological dad (and mom for that matter) is completely unknown.
- Doing In the Wizard: Pretty much anytime any character references something occurring spiritually, expect Senku to give the actual scientific explanation.
- Emperor Scientist: A benevolent version. He's able to get many characters and entire communities on his side just by showing them what the old world could offer with technology.
- Enemy Mine: Has chosen to work with Xeno in solving the mysteries of the Petrification Event and Whyman, while Xeno waits for Stanley to rescue him.
- Einstein Hair: Exaggerated to its logical extreme. Senku himself is, of course, a fan of Einstein and bases some of his creations on his work. One of the cover art pages even features Senku dressed as Einstein and doing his signature tongue-poke. In chapter 93, Senku also does the pose for the first photograph taken since the petrification.
- Fake-Out Make-Out: When Kohaku gets into a fight with Kirisame and realizes she's both in over her head and possibly about to blow their cover, Gen bails her out by getting her to kiss Senku and trick Kirisame into thinking she's just a lost girl looking for her boyfriend. Considering Kohaku and Senku are both Celibate Heroes though, both of them are... not particularly into it.
- Family of Choice: While it was already established that they weren't blood-related, Chapter 115 reveals that Senku was apparently the child of Byakuya's best friend. He doesn't know anything beyond that, but he really doesn't care because it doesn't matter to him; he and Byakuya were father and son.
- For Science!: Senku lives by this trope. Early in his childhood he was fascinated by science and technology, and worked hard to master it. Once he reawakens in the stone world, he utilizes his previous education and experiments to try and bring humanity back to the technological level they were at before the world turned to stone. He has hits and misses, and we're shown not just when he succeeds, such as when he first recreates a light bulb, but also failures, such as his first attempt to melt iron filings down into an iron bar, but fails because they can't heat the forge up enough to cause it to melt. Despite those setbacks, Senku says trial and error is part of science, learning what works, and what doesn't.
- Freudian Trio: The Superego (very logical and interested in rules (of science!)) to Taiju and Chrome's Id (much more emotional and given to impulses them him) and Kohaku and Yuzuhira's Ego (a balance between the two, each in their own way).
- The Gadfly: Aside from his intelligence, one of Senku's defining characteristics is how much he enjoys using his knowledge to screw around with people and piss them off just for the sake of it.
- Geek: Besides being scientifically minded, he's clearly a fan of video games (name-dropping Monster Hunter and Dragon Quest in specific) and anime (including Doraemon, Gundam, and Dragon Ball).
- Geek Physique: He's a genius, and while he has a slim, athletic body, he's not very strong or muscular. Or at least, compared to everyone else.
- Given Name Reveal: His last name is revealed in chapter 41 to be Ishigami. Which is a spoiler, because before that fact is revealed, we learn that the stone village he's been staying in for the past six months is called Ishigami Village.
- Go Mad from the Isolation: Averted. Despite remaining fully conscious and petrified for 3,719 years, he emerges as spirited and snarky as ever. He even spends an additional 6 months alone before Taiju wakes up.
- Good Is Not Soft: If you're on his side, he'll gladly treat you like a friend and occasionally even go out of his way to make something to help you specifically, such as a pair of glasses. If you're not, you're getting the blunt of his scientific advances, as Tsukasa's goons find out.
- Handshake Substitute: He tends to do high fives, but there's a greater significance behind them than just saying "hello". If Senku high-fives you, it's him metaphorically tagging you in; it's his symbol that he has complete trust and faith in your abilities. A few characters like Kaseki and Suika have picked up on this, and actually asked for (and received) high fives before starting on some important job.
- Happily Adopted: Not related to his dad by blood, but they got along great before the petrification event separated them.
- Heroic Sacrifice: Even knowing that Tsukasa will kill him once he has the revival formula, he tells it to him anyway so he can let Yuzuriha go free. Tsukasa then proceeds to strike his neck with enough force to kill him... which would have been successful had Senku not had a small, hidden piece of stone still left on his neck.
- Hellbent For Leather: His clothing is made from leather he obtained by killing and skinning wild deer.
- Hidden Heart of Gold: Despite his eccentric personality and ego over his intelligence, Senku does have the goal of restoring humanity and cares about Taiju and Yuzuhira. He even keeps his promise to Gen and makes him a bottle of cola.
- Honey Trap: Hilariously and to everybody's immense surprise considering his usual disinterest in romance, he proves perfectly capable of charming The Mole Luna as sort of an insurance policy against Xeno's plans, breaking out the Bishie Sparkles on her and everything. Which proves to save his life when he gets shot and Luna- the only medic around- decides to treat him.
- Insufferable Genius: He is always certain of something at ten billion% in the bag, and is not shy about reminding people just how smart he is.
- Jerk with a Heart of Gold: While he generally looks down on people due to being so much smarter, he does genuinely care about Taiju and Yuzuriha, and while he may sound like a Mad Scientist, he disproves Tsukasa of having any sort of misanthropy, with his goal having altruistic motives.Senku: I am a technology loving kid, who's excited by mecha, space, and Doraemon! I will save all of humanity, without exception, with the power of science!
- There's also the fact that when he make glass, he decides the first thing he'll do with it is make Suika glasses.
- As exemplified by the quote, despite his superiority complex, Senku's long term goal is to restore humanity from stone.
- He may tease Taiju a lot, but it's clear that Senku has absolute faith in his friend. The gasoline "love potion" prank may seem extreme, but afterwards Senku explains that he only offered it because he knew Taiju was too honest and noble to even consider using such a thing. He also believed that Taiju's confession would succeed (when everyone else thought he'd get shot down), and knew that Taiju would be able to overcome the petrification because his pride as a man wouldn't let him accept his confession being interrupted.
- Despite somewhat cruelly mocking Chrome because it was likely Ruri would end up marrying Kinro or Ginro, Senku does help him win his fight in the tournament when the time comes. Furthermore, when he actually ends up winning the tournament and marrying Ruri, he immediately finds a reason to divorce her rather than try to take advantage of the situation (it helps that he's a Celibate Hero, though).
- When trying to win over the trust of Ishigami village, Kohaku frequently remarks how he sounds like an evil villain out for conquest when he talks about it, despite it ultimately being beneficial for everyone involved.
- There's also the simple fact that he's the World's Smartest Man without being an Insufferable Genius (except for brief comedy beats). Quite the opposite, Senku recognizes that progress takes all kinds of people and readily acknowledges those who possess skills he lacks, praising Kaseki as a master artisan, nicknaming Suika "Great Detective" for her investigative skills, and entrusting Yuzuriha with the secret mission to fix the statues Tsukasa and his people broke because he respects her precision and skill with handicrafts.
- Late-Arrival Spoiler: His surname, a major reveal near the end of Part 1, is used frequently in promotional material from then on.
- Lethal Chef: Zig-Zagged. He knows how to cook, but due to lack of experience and the quality of the ingredients at hand, Senku's more complex dishes like ramen and bread tend to taste horrible to anyone but the villagers of Ishigami Village. At one point, his cooking is literally likened to a Fate Worse than Death, with starvation due to people refusing to eat his cooking being presented as an actual threat, convincing the modern-timers that having a Supreme Chef on board is a vital necessity rather than a luxury. However, his attempts at making sweets like cotton candy and vanilla ice cream are far more successful and are loved even by the modern-timers.
- Mad Scientist: Definitely has shades of being one at least, as he tends to take great joy out of using people like guinea pigs for his experiments and he can put on some pretty twisted facial expressions when something scientific intrigues him (as Kohaku often notes). However, it's ultimately Subverted because, despite his trolling nature, he's ultimately got a good heart and has no real interest in using his science to hurt people.
- He has a knack for building crazy things on the fly to help him out in tough spots, such as a cart contraption to make transporting himself and Kohaku to her village easier.
- He defeats Ginro in the village games by balancing his staff on Suika's mask to create an impromptu simple-lever machine, delivering one hell of a Groin Attack by stepping on it at just the right time.
- Magnetic Hero: A unique variation, but one nonetheless. Despite being an Insufferable Genius and Jerk with a Heart of Gold with little if any social and emotional tact, his scientific expertise, recreation of creature comforts from technology, and very genuine desire to restore civilization and save EVERY single human (unlike Tsukasa) causes multitudes of people to flock to his cause, and even persuades many initial adversaries to join him.
- Manly Tears: He briefly sheds tears at his father's grave before recomposing himself and returning to the village.
- Master of All: If there is a subject of science he hasn't displayed expertise at, then Senku has simply never gotten the chance to display it.
- Meaningful Name: His surname, Ishigami, means 'stone god'.
- Missing Mom: Back in 2019, his dad only mentioned Senku when Lilian asked him about his family, and Senku's mom has not been seen in any flashbacks. Of course since Senku and Byakuya aren't blood related, it's possible Byakuya never married and raised Senku by himself.
- Not So Stoic: He may be intelligent and science-minded, but he still has some classic Shonen Jump traits like absolute faith in his friends and an understanding of Pridenote . Tsukasa calls it his weakness, since he can't be truly objective and logical when his friends' lives are on the line.
- Senku's hair on the cover pages has gone from being blond◊, to light-green◊, to finally white◊. According to Word of God, it was always intended to be white, so all other depictions were inaccurate. The anime went with the "white fading to green" version.
- He's much more muscular on the cover of chapter 1 than he is in the actual series, though that could just have been an artistic decision.
- Omnidisciplinary Scientist: Senku is not only an accomplished engineer, physicist and chemist, since he's been building rockets on his own since childhood, but is also knowledgeable in geology, biology, and of course mathematics. At this point, there's no telling what other areas he has mastery over.
- One-Man Industrial Revolution: The central plot revolves around Senku, using his vast scientific knowledge, attempting to drag the current stone age world kicking and screaming back into the modern era level of technological advancement. So far, he is handily winning this struggle.
- Our Hero Is Dead: Briefly suffers this early on when Tsukasa seemingly delivers a fatal blow to his neck. It turns out a few chapters later he had a plan to come back to life.
- The Pollyanna: While he isn't as energetic and outwardly positive as this trope implies, Senku utterly refuses to let anything disrupt his optimism regarding what's possible for him to reinvent and the resurrection of all of humanity.
- Pretty Boy: He's canonically considered quite attractive In-Universe by many women; even Kohaku has to admit that he has the look of a "lady killer". Befitting his genius, he quickly uses his looks to his advantage against the American Science Kingdom spy Luna, uncharacteristically turning up the charm on her when he senses her Single Woman Seeks Good Man tendencies.
- Really 700 Years Old: Senku is around ~3,737 years old, having spent 3,719 years fully conscious during his petrification and counting the seconds. Despite this, his body didn't age a day and he more or less still acts like a teenager (or at least, you know, how a teenager with a genius level IQ would act). Lampshaded when he makes wine: Taiju tells him that teenagers shouldn't drink, and Senku replies that since he's over 3700 years old, he's technically an adult by now.
- Reused Character Design: Senku looks like a miniature version of Ken, hell, even when he's drawn as an adult◊, or with a suit◊ he looks even more like him.
- Science Hero: While he may come off as an egotistical jerk, he really does want to restore as much of humanity's science as he can, and create a kingdom for science. To do so, he mostly uses his knowledge to create tools that will help him and his allies.
- Sharp-Dressed Man: While the Stone World has forced him into wearing simpler clothing, the What If? cover art (which features the village characters and Senku in the past) shows that his natural fashion sense leans towards sharp suits. And thanks to Yuziriha's skills as a tailor, he eventually gets the option to dress up once again, choosing a dapper suit when he plays Ryusei in their ship's casino for example.
- Signature Laugh: Kukuku
- Spell My Name with an "S": "Senku" or "Senkuu", depending on which transliteration convention you use. Although the official translations use "Senku", the spelling "Senkuu" can be seen in some places, such as on the side of the rocket he made in his childhood.
- Squishy Wizard: Teen Genius he may be, with enough scientific knowledge to potentially restore civilization, but compared to just about everyone around him, his physical abilities are practically nonexistent.
- Teen Genius: As a former Child Prodigy, he was naturally just as brainy during his high-school years. Even today, he's most likely still a teenager; assuming he was frozen at 15 or 16 (it was revealed that the stone incident happened 5 years after his 5th-grade year), he should currently be about 17 or 18 (technically, at least).
- Thanatos Gambit: He anticipated Tsukasa's FaceHeel Turn and started performing a Character Tic that drew attention to his neck; when Tsukasa attempted to give him a quick and painless death he struck that precise spot. After getting away Taiju and Yuzuriha discover a tiny patch of petrified skin at the base of Senku's neck and figure out that he was specifically baiting Tsukasa to strike him in that spot because they could use the secondary healing aspect of the depetrification process to bring him back to life, which would buy them some (but not much) breathing room while Tsukasa still believed him dead.
- Troll: Senku really likes screwing around with his friends. A stand out example, though, would be when he rubs it in Chrome's face that his crush Ruri is probably going to end up marrying Kinro or Ginro due to their village's customs.
- Tsundere: He's a lesser example of a Harsh type, tending to put on a tough-guy act and say things like "I invented this to help myself, any benefit you get is secondary". However, he's also very open about how much science improves peoples' lives, and the affection he has for the villagers makes it clear that he isn't nearly as harsh as he sounds.
- Two Guys and a Girl: Has formed a trio like this with Taiju and Yuzuriha for most of his life, including the events of the first arc in the manga. He also quickly forms one with Chrome and Kohaku after meeting them.
- Vitriolic Best Buds: With Gen. The two viciously banter often, but it's clear they greatly value each other's friendship and respective abilities, and trust each other greatly in difficult situations.
- Weak, but Skilled: Not only does Senku have no fighting or hunting capabilities like Taiju, but he also lacks physical strength and endurance.note However, Senku is possibly one of the smartest and most educated people on the planet, and he's definitely the smartest person left in the Stone World. As such, despite his lack of physical power, he's the only one left in the world capable of kickstarting the recreation of civilization. Tsukasa knows this, which is why he's far more concerned about Senku rather than Taiju.
- Will Not Tell a Lie: According to him "Science doesn't lie", and neither does he when it comes to science, even in situations where doing so would benefit him. Early on, when Tsukasa holds Yuzuriha hostage and demands to know the formula for the "miracle water", Senku complies rather than giving him a false formula just to save his friend. When they're trying to sway Nikki to their side, she asks if they can bring back Lillian Weinberg's music; Gen encourages him to lie and say yes, but Senku admits that all music storage media from their time have long since crumbled into dust. It also works the other way around: he won't lie to give someone false hope, meaning if he says it's possible to save someone's life he really means it, as seen with both telling Tsukasa that de-petrifying his sister Mirai might restore her from clinical brain death, and later telling Mirai that they can use the "stone beam" to save Tsukasa from the mortal wound Hyoga inflicted upon him.
- Wise Beyond Their Years: While his great intelligence is often pointed out, what's equally noteworthy is that Senku is rather calm, patient, and sagely whenever he needs to be. Some good examples would be his various speeches to Chrome about what it means to carry on the will of science in the event of his (Senku's) death.
- World's Smartest Man: Genius Bruiser Tsukasa has called him the smartest person he has ever met. The unparalleled expertise he's displayed in various fields of science without modern technology to aid him only supports this status. After he awakens after 3700 years, he immediately starts using his vast scientific knowledge to re-discover everything from metalworking, agriculture and sailing to telephones, radar, and even soda pop, all while trying to find a way to undo the petrification process and save humanity.
- Xanatos Speed Chess: He is a master at analyzing tough and even impossible situations, and coming up with solutions and strategies on the spot. Which is fortunate because, due to his Born Unlucky status, his long-term plans never turn out the way he intended.
- During the climax of the Stone Wars arc when all seems lost Senku is able to make nitroglycerin and force Tsukasa's forces to surrender
- In Chapter 127 he is able to properly deduce through pure logic that Kirisame is throwing a fake petrification weapon, and to order an emergency evacuation fast enough for it to be effective with no casualties. Not only that, but he later uses Magma's betrayal and him going full Leeroy Jenkins to his advantage in order to turn the situation around.Senku: It's when your back is against the wall that your chance truly comes, right?
Voiced by: Makoto Furukawa (teen), Mutsumi Tamura (child) (Japanese), Ricco Fajardo (teen), Emily Fajardo (child) (English), Miguel Angel Ruiz (Latin American Spanish)
Senku's best friend. Though nowhere near as intelligent as him, he makes up for it with his strength and endurance, and is fiercly loyal.
- Anchored Ship: Him and Yuzuriha. Despite obviously liking each other, Taiju decides not to ask her out because they're basically the last people on Earth and he doesn't want to make her feel like she has no other choice.
- And I Must Scream: Unlike many others whose consciousness faded over time after being frozen, Taiju stayed awake during his entire petrification by thinking about Yuzuriha. However, he ends up just fine after waking up.
- Badass Pacifist: Despite his massive strength and endurance, he refuses to fight anyone because he doesn't want to hurt people.
- This is later Played for Laughs, when he first fights Tsukasa, where he declares that he won't fight back, but will allow Tsukasa to keep hitting him as long as he stops breaking statues; however, the sheer lack of logic only confuses Tsukasa.
- The Big Guy: Of Senku's crew. Taiju's physical capabilities are roughly on par with Tsukasa's, given that the latter considered him a serious threat if angered, and though he lacks any will or ability to fight, his toughness and endurance are so absurd he even shocks the stone world inhabitants.
- Book Dumb: Taiju's never going to be a scientist or a scholar, he just simply does not get concepts and theories. But he's aware of his own shortcomings, and not only does he have a decent track record with finding "mundane" solutions that he can perform without science, he also tends to remember things Senku says that he can understand. Taiju might not get why something works, but he can still act on the knowledge that it does. For example, he ends up having the most successful wheat field, simply because he remembered a conversation he and Senku had years earlier, where Senku offhandedly mentions that crushed seashells can improve soil qualitynote .
- The Bus Came Back: At the beginning of the Stone World War arc, he and Yuzuriha return to help Senku fight for the Cave of Miracles.
- Call to Agriculture: When Ishigami Village starts growing their own wheat, Taiju takes to it like a fish to water — not just because of his bottomless stamina, but because that kind of straightforward, honest work fits his personality perfectly and because it's the best way he can help rebuild humanity by ensuring that there's enough food to go around.
- Cannot Spit It Out:
- He spent all of his childhood and most of his teenage years being unable to tell Yuzuriha how he felt. Then, at the very moment he was finally about to confess, the stone explosion happened and he was petrified. It was his resolve to tell her how he felt, in fact, that kept him conscious for thousands of years until he eventually broke free.
- After finally reuniting with Yuzuriha, however, he's now decided that he won't ask her out because they're basically the last few people on the planet and he doesn't want to make her feel like she should be obligated to say yes.
- Charles Atlas Superpower: Crossed into this territory around chapter 11, when he takes this◊ huge rock and throws it a good 6 meters or so directly up into the air. Not even the finest shot-put athletes in real life could do that.
- Childhood Friends: With Senku and Yuzuriha, and he eventually fell in love with the latter.
- Crouching Moron, Hidden Badass: Despite his lack of intelligence, he can prove to be resourceful in his own way when push comes to shove.
- Decoy Protagonist: The first chapter is told almost entirely from Taiju's perspective. Afterwards, however, he becomes the group muscle while Senku establishes himself as the protagonist.
- Determinator: If there's one thing he and Senku share in common, it's their determination. Like Senku, he stayed conscious during the entire 3,719 years he was frozen via thinking of his love for Yuzuriha. He also survives a blow from Tsukasa without any long-lasting effects.
- Dumb Muscle: Frequently pointed out by Senku, he has ridiculous strength, but is dumb as a stump about most things.
- Easily Impressed: Pretty much every science-thing Senku does amazes him to no end, even simple things like using sea salt for food seasoning. Typically, this elicits either appreciation or snarky gloating from Senku (emphasis on the latter).
- Go Mad from the Isolation: Again, Averted, like Senku. Despite being fully awake for almost 4,000 years and unable to move or interact with anybody, Taiju's mental state remains fine after finally freeing himself.
- Heroic Build: In contrast to Senku's wiry build, Taiju is built like a tank of solid muscle. He's perhaps only beaten in this aspect by Tsukasa.
- Hot-Blooded: He definitely does the most shouting and he's extremely passionate about his faith in Senku.
- Large Ham: While there are occasional situations where he can be calm and collected, around 90% of the time his voice is full of enthusiasm and volume.
- Made of Iron: The only person to ever take a hit from Tsukasa and stay standing.
- Nerves of Steel: Surprisingly, despite being very emotional and expressive, Taiju has great control over his anger; even when Tsukasa directly threatens Senku and Yuzuriha, he never loses his cool or composure. This shocks even Tsukasa, who was fully expecting Taiju's wrath after he "killed" Senku.
- Nice Guy: One of the kindest characters in the series, he can even put up with Senku.
- Pre-Mortem One-Liner: Subverted. He says "farewell, Tsukasa" before seemingly engulfing him in a huge black gunpowder explosion, but as Tsukasa quickly puts together, he actually had no intention of hurting him; he knew that Tsukasa would survive and he actually just meant "farewell" in a benign sense.
- Put on a Bus: At the beginning of the Stone World: Origin arc, he leaves with Yuzuriha to keep an eye on Tsukasa.
- Really 700 Years Old: Taiju is around ~3,739 years old, having spent most of the last 3,721 years fully conscious during his petrification by thinking of his resolve to declare his love to Yuzuriha. Despite this, his body didn't age a day and he more or less still acts like a teenager.
- The Reliable One: Taiju may be Book Dumb, but he has the endurance and the patience to work literally all day long on whatever Senku needs him to, even if he himself doesn't understand what he's working towards. Also, despite being a very emotional guy, he showcases a lot of self-restraint and emotional control when it comes to enacting Senku's plans. On top of all this, his trust in and fondness for Senku allow Taiju to follow his lead and understand his orders on the fly with even the barest of hints. All in all, Senku couldn't ask for a better friend.
- Stone Wall: Taiju can take a beating easily, but he has no skill in fighting or even the capacity to hit another human being. His solution to dealing with Tsukasa was to allow him to "beat him as much as he wanted" if it meant he would stop killing statues. Tsukasa, being The Spock, is simply confused as he can't see the logic behind that.
- Two Guys and a Girl: Has formed a trio like this with Senku and Yuzuriha for most of his life, though he's been in in love with the latter since elementary school.
- Undying Loyalty: Taiju completely entrusts his life to Senku, and would gladly give up his own life if it means saving Senku's. Same goes for Yuzuriha.
- Unskilled, but Strong: Taiju has none of the scientific knowledge necessary to help recreate civilization and he has no skill at all in fighting or hunting, but he's as strong as an ox and his body is built like a tank. As such, he's most useful handling the demanding physical labor that Senku and Yuzuriha can't do. Furthermore, despite his lack of fighting skill and killing intent, his durability and strength is possibly comparable to Tsukasa himself. As such, while Tsukasa is more worried about Senku than Taiju, he does admit that it would be dangerous if Taiju were to lose control and come at him with full-force.
Voiced by: Kana Ichinose (Japanese), Brittany Lauda (English), Jessica Angeles (Latin American Spanish)
The Childhood Friend of both Senku and Taiju and the girl Taiju loves. She is revived soon after Taiju and Tsukasa.
- Beauty Is Never Tarnished: Yuzuriha's mark is on her shoulder, rather than her face.
- Boring, but Practical: Her exceptional textile abilities don't initially seem as impressive as Senku's vast intellect, Taiju's inhuman strength, Gen's impressive mentalism, etc. But it's undeniable that cloth making is one of the cornerstones for the development of humanity, which means that Yuzu is a massive help for the making of different inventions.
- The Bus Came Back: Alongside Taiju, she reappears at the start of the Stone World War arc.
- Catchphrase: She tends to say "Wow", even when not surprised.
- Girl Next Door: The kind girl who Taiju knew since childhood and eventually fell in love with.
- Fashion Designer: Once she gets proper cloth to use, she basically invents fashion. Senku exploits it to make money for the Kingdom of Science.
- Hartman Hips: As is usual with the Boichi's tastes. She's the first major female character in the series, so naturally it's her hips that get all the attention before any other girls show up.
- Hidden Depths: Chapter 102 shows that not only can she endure Senku's multi-hour scientific lectures, but she actually enjoys them and can keep up with the science fairly well.
- Masculine Lines, Feminine Curves: Invoked. Her own marks look like swirls, as opposed to Senku and Taiju's marks that look like lightning bolts.
- Mundane Made Awesome: Her talent for arts and crafts is such that, with the limited tools available to her, she can sew together multiple sets of clothes in a matter of seconds, looking like a refugee from Jojos Bizarre Adventure all the while. What makes this even more awesome is that the sewing is just a feint. She pretends to need all night in order to make the clothes and uses the rest of her time piecing together the statues that Tsukasa and his soldiers have been shattering.
- Nerves of Steel: When Tsukasa holds her hostage, he cuts her long hair to intimidate Senku into giving up the revival fluid recipe. Yuzuriha responds by claiming he did her a favor, redirects his stone blade at her own neck, and makes it clear she's willing to die if it means Senku won't have to tell him anything. Fortunately, Senku has other plans...
- Also exemplified in another fashion when she pieces together the statues Tsukasa destroyed. Reviving a shattered statue requires there to be no missing internal pieces and no pieces out of place, and Tsukasa breaks statues down into gravel. Yuzuriha even admits that this task is grueling, but all of the statues she puts together were revived, showcasing her incredible willpower and concentration.
- Nice Girl: She's a sweet, kindhearted, and empathetic young woman, certainly part of the reason Taiju fell in love with her. On the day of the stone incident, she even tried to take a petrified bird to the veterinarian before school (as did Taiju separately).
- Not So Above It All: She gets ridiculously fired up when it comes to crafting projects, as seen when Senku asks her and Kaseki to make a 3D model of the Earth for one of his plans and they go completely overboard.
- Plucky Girl: After being unpetrified, she reacts to the new world fairly well, offering to help Senku and Taiju however she can.
- Put on a Bus: Along with Taiju, she leaves at the beginning of the Stone World: Origin arc to keep an eye on Tsukasa
- Textile Work Is Feminine: Was a member of the handicrafts club prior to petrification.
- Will They or Won't They?: With Taiju. She mostly reciprocates his affections but given the premises, Taiju doesn't want her to feel any obligation to accept.
Voiced by: Kengo Kawanishi (Japanese), Brandon McInnis (English), Brandon Santini (Latin American Spanish)
- Adaptation Dye-Job: The lighter end of his hair has gone from gold in official artwork to white in the anime.
- All Men Are Perverts: During his introduction, he somehow manages to creepily hit on Kohaku in the middle of being threatened with having his throat slit (by her, no less). He later goes on to say that all he really wants out of Tsukasa and Senku's conflict is to find a cozy place to stay and cute girls to keep him company.
- Attractive Bent-Gender: When the gang tries to create suitable candidates to infiltrate the Head's harem of girls, Gen proves to look really convincing as a girl and can even change his voice to match the part. Unfortunately for the sake of the mission though, he's apparently too tall to make a fully convincing girl.
- Astonishingly Appropriate Appearance: His scar is abstractly mouth-shaped. On certain zoom-ins on his face, it becomes noticeably spikier, like it's baring fangs.
- Big Damn Heroes: He recovers from his injuries in the nick of time and distracts Magma long enough for Chrome's plan to work.
- Birds of a Feather: Once he joins Senku's Kingdom of Science, the two of them get along like a house on fire, often exhibiting similar mannerisms and sharing a love of trolling their friends. Senku is always quick to catch onto Gen's schemes, and often assists in their execution.
- Bunny-Ears Lawyer: He's lazy, self-absorbed, and a playboy, as well as a willing turncoat if it secures his own comfort. However, he is at his core a genuine magician and mentalist, both skills being used to distract and manipulate people on levels that have even saved other characters' lives.
- Celebrity Survivor: Like Tsukasa, he was famous in Japan before the Stone World, being a well-known magician and author.
- Chekhov's Gunman: Appeared on the cover of his book, "Magic Psychology", in a flashback in chapter 12. He would properly debut on chapter 23 as Tsukasa's spy, and someone Senku would have to convince to join his side.
- The Chew Toy: Whenever hard or tedious labor is required for one of Senku's invention, it's typically Gen who gets roped into doing it.
- Consummate Liar: His defining trait; he's a self-described "mentalist" (more of a showman/magician as Senku puts it) with a good understanding of human nature, and so he's easily able to trick people and sway things to his favor with his words. He's not called the "silver-tongued man" for nothing, after all. In chapter 151, it is shown that not even a polygraph machine can detect his lies, although Dr. Xeno still becomes suspicious because of how honest he's being.
- Cowardly Lion: A non-combative subversion. He generally avoids danger and is overly cautious not to get caught up in a situation that would immediately put his life at risk, but he still goes into a Battle of Wits with Moz in order to make a deal with him and prevent him from going full Blood Knight on the entirety of Senku's party. He seems cool and collected while doing so, but his subsequent reaction once Senku's party is out of harm's way, reveals that he is very much this trope. He still didn't get to throw a single punch, but what he managed to achieve require guts.
- Crazy-Prepared: Apparently, he walks around with protective padding and packets of animal blood under his clothes in the event of a surprise attack. And, sure enough, this allows him to survive an assassination attempt by Magma.
- Creepy Good: Dude can't even plan a birthday party for a friend without going into some kind of "Evil Planning Mode," complete with Nightmare Face.
- Does Not Like Shoes: Like Tsukasa, Gen doesn't wear shoes. However, unlike Tsukasa, Gen would probably love to wear shoes. Keep in mind that he had to walk around 80 km barefoot to get to the village, and he's not an overpowered freak of nature like Tsukasa. This may or may not have contributed to his switching allegiance to Senku's kingdom of science. He's later seen wearing shoes like Senku's and Taiju's after defecting to the Kingdom of Science.
- Good Is Not Soft: Like Senku, he isn't afraid of using his field of expertise against people he's against, as seen as when he sabotages Magma and Hyoga early on. However, those on his good side get his upmost respect, Senku, in particular, being gifted a telescope on his birthday out of Gen's own kindness.
- Guile Hero: Gen has profound knowledge of human psychology, which lets him read and manipulate other people with ease. Once he pulls a HeelFace Turn to the Kingdom of Science's side, he takes upon this role, contrasting the Science Hero Senku.
- HeelFace Turn: Ends up loyal to Senku and lying to Tsukasa about his survival when promised some soda.
- Hidden Depths: He was smart enough to figure out Senku's birthday, based on only two pieces of evidence: the date of his revival (which he carved into a tree) and a single conversation where he casually mentioned how many days old he was.
- Faking the Dead: He plays dead after being stabbed several times by Magma, having survived through the various cushioning on his body and selling it through packets full of animal blood.
- Flower Motifs: He's heavily associated with nightshade, which means "liar" in flower language. He proclaims it's his favorite plant.
- Foil: To Senku. Both are from the modern era and were considered "geniuses", except Senku's was in a more straightforward field while Gen was a master in psychology. Senku is very blunt with people but is genuinely well-intentioned, while Gen is a skilled manipulator and is easily swayed through appealing to personal comfort. Senku is also a Celibate Hero while Gen is a Covert Pervert.
- The Lancer: Like Chrome, he's relatively on-par with Senku and becomes his left-hand man and commentator over the scientist's antics.
- Locked into Strangeness: Back in 2019 his hair was all black (as seen on a magazine cover), but after being revived from petrification it's gone half-black and half-white.
- Meaningful Name: The "Gen" in his name means "illusion", while the "Asa" means "frivolous" or "superficial"
- Mundane Utility: He was a stage magician and mentalist in the old world. In the new world, he frequently applies his skills in the latter to ensure that Senku's Kingdom of Science runs smoothly, using his skills to induce cooperation, cultivate enthusiasm, and conduct negotiations. Because of this, he soon becomes an essential element in the smooth running of several of Senku's schemes.
- Nerves of Steel: As noted by Kohaku, he's visibly not nervous at all when being threatened with spears, despite claiming otherwise. This is probably because he has all sorts of cushioning on his body that allow him to survive in the event of a stabbing. And possibly due to his confidence in his ability to manipulate people.
- Obfuscating Stupidity: He's shown to fire back and forth between his true colors as a deadpan manipulator to a ditzy airhead.
- Opportunistic Bastard: Although he works for Tsukasa, he's not shy about letting Senku know that he'll change sides if Senku's kingdom of science seems more appealing. True to his word, he was impressed after seeing the creation of an electric lightbulb, but fully joins Senku's side once he was promised he would receive some delicious Cola.
- Pig Latin: The Viz translation and the English dub give him this as a quirk in his speech.
- The Mole:
- Takes on this role after deciding to side with Senku's kingdom of science, pretending to be loyal to Tsukasa while undermining his forces from within. His deception is exposed when he sabotages Hyoga's weapon.
- He once again plays this role in America, infiltrating Dr. Xeno's base to gain information about the enemy.
- The Social Expert: He once wrote a book on psychology, and uses this knowledge to manipulate people.
- Stage Magician: What he was famous for before the Stone World. Nowadays though, he actively takes advantage of his skills to trick the primitive villagers into thinking that he really is a sorcerer.
- Straight Man: Acts as this whenever Senku proposes a seemingly impossible contraption to build, like a telephone or a car, since he's usually the only other de-stoned person around to know how ridiculous those ideas sound.
- Token Evil Teammate: Downplayed. While not outright malicious, whenever Senku is facing an obstacle that requires less than ethical means to solve, Gen can usually be expected to back it if he didn't suggest it to Senku himself.
- Trademark Favorite Food: He betrays Tsukasa and joins Senku in exchange for a bottle of Cola.
- Verbal Tic: He swaps the syllables of certain words, for instance saying "doihi" instead of "hidoi" (which means mean, harsh, or terrible). The Viz translation and the English dub approximate this with Pig Latin.
- Vitriolic Best Buds: With Senku. The two viciously banter often, but it's clear they greatly value each other's friendship and respective abilities, and trust each other greatly in difficult situations.
- Voice Changeling: Gen is very talented at imitating voices. His Tsukasa impression appears to unnerve even Kohaku, and he can even do a woman's voice, like when he imitates Lillian Weinberg as part of a plan to pacify the Tsukasa Empire's army.
Heir to the now extinct Nanami conglomerate and director of ocean-based Nanami school, depetrified by Senku for his unrivaled captaining skills.
- Ambition Is Evil: Subverted in that Nanami is very greedy but generally his greed means that he pushes for further developments that help everyone. His butler Francois deeply respects his ambition as he's willing to put in the work to get what he wants.
- Bunny-Ears Lawyer: He was a globe-trotting playboy and an exceptional sailor by his mid-teens. Nikki summarizes the trope rather effectively by describing him as "over-the-top but incredibly talented".
- Character Tics: Constantly snapping his fingers.
- Chivalrous Pervert: He has a thing for beautiful women, but he considers all women beautiful and does everything he can to ensure their happiness, including getting stable food supplies for Ishigami Village so they'll never have to lose family to famine again.
- Cruel to Be Kind: When he discovers that Suika stowed away on the science vessel Perseus, Ryusui absolutely refuses to let her stay, saying that they're taking her back to Ishigami Village at the next opportunity. However, afterwards Francois explains to Suika that he's being stern because they're in the middle of a dangerous mission and he'd never risk a child's life. When the ship gets attacked by people with the "stone beam", Ryusui's last act is to get Suika to safety, and after they de-petrify him he praises her for a job well done under difficult circumstances.
- Determinator: One of the positives that come from his greedy nature is that Nanami does not give up on the things that he wants. And while that would be bad in most circumstances, Nanami's greed extends to the people around him as well. One of his goals is to never see a beautiful woman cry again, and he considers every woman he's seen thus far beautiful, even the elderly.
- Fiction 500: The conglomerate he was part of was rated as valuing of 200 trillion yens, approximately 1.8 trillion dollars. He immediately works to recreate this, demanding monopoly of any oil found and printing money backed by his oil.
- Greed: His primary character trait, though it's not always treated as a problem since it gives him the drive to help rebuild society so that he can live in wealth and luxury again. Later on, Nanami makes it clear that, at least in his case, it's a truly positive trait. He's so greedy that he wants the best not only for himself but for everyone around him. The extent of his greed is so great he can be greedy on behalf of other people.
- Hidden Depths: His debaucherous lifestyle is funded by money he made HIMSELF through the stock exchange, gambling, various competitions, etc.
- I Know Mortal Kombat: Playing video games has trained him to shoot a gun while simultaneously piloting a plane.
- Literally Shattered Lives: In Chapter 116, after being re-petrified by the villains on Takarajima, Kohaku breaks him into small pieces so she can ship him back to Senku in his "mouse drones". They put him back together and de-petrify him shortly thereafter; it helps that Kohaku broke him very precisely to make it easy and avoid small fragments chipping off.
- Meaningful Name: 'Nanami' literally means "Seven Seas", and "Ryusui" means 'Water Dragon'— so, his name can be read as "Water Dragon of the Seven Seas", a fitting name for a captain.
- Nice Hat: A captain's hat.
- Non-Action Guy: Like Senku, but Ryusui is far more notable because he's inexplicably jacked just like Tsukasa or Taiju despite not being a fighter or a laborer.
- Power Copying: One of the potential applications of his greed is that if he sees someone use a skill which he desires, he can learn it very quickly. This allows him to copy his opponents dogfighting techniques after seeing them just once in chapter 164.
- Scars Are Forever: As with every character released from stone, he has a form of scarring on his body from the process; in his case, his entire right hand looks like it was dipped in ink palm-first, seemingly representative of his greed in the stone world. After being petrified and restored a second time in the Treasure Island arc the scars are gone, suggesting that they were the product of thousands of years of weathering.
- Silly Rabbit, Cynicism Is for Losers!: In Chapter 124, after Senku finally invents firearms, Ukyo says that he still wants to avoid bloodshed, fully expecting that the others will think his idealism is foolish in such a dire situation. However, Ryusui says that Ukyo's attitude is completely logical, since killing people just makes enemies of their friends and family, which is why they aren't going to kill anyone with their gun.
- Taking the Bullet: During the Treasure Island arc, he's taken out of commission when he kicks Suika out of the way and off the boat before he and the others on the boat got petrified by the petrifying device.
Nanami Ryusui's butler. A faithful and extremely talented servant whose services were in high demand before civilization fell.
- Ambiguous Gender: To the point where nobody knows if Francois is a Bishōnen or a Bifauxnen. Even Nanami has no idea, though in his case he simply doesn't care.
- Foreshadowing: Is mentioned when Nanami reflexively tells Francois to write Senku and the others a check as thanks for freeing him from petrification but doesn't properly come into the story until it's determined that they need a chef.
- Supreme Chef: The reason why Team Science needs to resurrect Francois since they need someone who can prepare long-lasting rations for their upcoming sea voyage.
- Undying Loyalty: Fittingly for a butler held in such high regard, from the moment Francois is restored, Francois' only concern is how to fulfill Francois' employer's desires. Even after Francois wakes up in the stone world.
A small population of 40 non-petrified people in the Stone World, who Senku encounters while investigating the source of smoke signals, gradually recruiting them (and the rest of the village) into his Kingdom of Science with his various re-discoveries of lost inventions and technology.
- But Not Too Foreign: Senku and Tsukasa note that Kohaku and Ruri (and a lot of the other villagers) have foreign blood, but can't seem to place why. Turns out it's because they're descendants of astronauts who returned to Earth from the International Space Station in their Soyuz spacecraft.
- Rock Theme Naming:
- Everyone in the village is named after a rock or mineral. There are only three exceptions: Genbu, a nameless man (Though his name is revealed in chapter 100 to be Soyuz), and Suika. (Although Suika is a nickname, and her actual name has yet to be revealed.)
- It becomes a plot point later on - since they know the names of so many minerals, they must have even more in their village's lore. So Senku has their storyteller go over everything she knows regarding rocks and minerals.
Voiced by: Manami Numakura (Japanese), Felecia Angelle (English), Alicia Barragan (Latin American Spanish)
One of the village's fighters and caretaker of her sister Ruri. She's also the strongest fighter in the village. Kohaku takes a liking to Senku after watching him confront Tsukasa, then helping her after she is nearly crushed by a tree. She becomes Senku's first villager ally, although she is annoyed by Senku's personality.
- Action Girl: A fighter skilled and strong enough to even go toe to toe with Tsukasa.
- Animal Motifs: Is called a "lioness" by Senku, which fits her strength and dedication to the ones she loves. However, she hates being called that.
- Berserk Button: Hates being called a "lioness", but "gorilla" is even worse.
- Hearing that the top contender in a competition to be her sister's husband didn't care whether Ruri lived or died as long as he got to become the village chief sent her into such a rage that she was banished for attacking him.
- She seems to hate shallow or selfish men, as she immediately takes a disliking to Gen and frequently mentions that she wants to kill him whenever he says something smug. Likewise, on the opposite end of the spectrum, she takes a liking to Senku once she deems him a "gentleman".
- Big Sister Instinct: Technically Ruri is the older sister, but her sickliness means Kohaku is the one who has to protect her. She also has this dynamic with Suika, who she treats like a little sister.
- Book Dumb: Obviously she never had formal schooling, but Kohaku is still fairly clever and quick on the uptake. During the "Arithmetic Battle" bonus chapter she demonstrates at least a basic understanding of multiplication (since it's the easiest way to count large numbers of fish), and during the Treasure Island arc she gets around her illiteracy by sending Senku a Rebus Bubble message to tell him "The platinum is here."
- Cat Smile: Frequently, especially during comic beats.
- Celibate Hero: Aside from some mild flirtations here and there, she overall doesn't seem particularly interested in the whole dating thing, focusing more on protecting her friends and becoming stronger. It also helps that she's One of the Guys and all the men around her typically find her too tomboyish to consider pursuing.
- Cuteness Proximity: When she sees Suika's face for the first time she starts gushing over how adorable she is.
- Deadpan Snarker: She has her moments of snarkiness, usually when one of her male-friends is doing something stupid (which is, to say, very often).
- Fake-Out Make-Out: When Kohaku gets into a fight with Kirisame and realizes she's both in over her head and possibly about to blow their cover, Gen bails her out by claiming that she's a lovesick girl who freaks out when her boyfriend Senku isn't around. He then tries to get them to kiss to prove it, but considering Kohaku and Senku are both Celibate Heroes, neither of them are... particularly into it.
- Hair of Gold, Heart of Gold: She's actually really kind. Interestingly, most people from the village are blonde for some reason. Tsukasa even wondered if she is half-Japanese.
- Hartman Hips: Courtesy of Boichi. Lampshaded by Minister Ibara, who points out that Kohaku's "curviness" makes up for her rough personality (right before he very nearly gets his arm and hand snapped in half from attempting to grope her).
- Honor Before Reason: Despite knowing for sure that Mantle is lying about Suika drowning, Kohaku still runs off to save her, based on the very slightest chance that Suika might be in danger. When she discovers Suika was merely tied up but already escaped on her own, Kohaku fails to make it back to the Grand Bout in time for her match, disqualifying her and disrupting the Kingdom of Science's plans to win the tournament.
- I Resemble That Remark!: Anyone calling her a gorilla because of her strength and/or aggression will get smacked on the head, which Chrome points out is proof of her gorilla-ness.
- Identical Granddaughter: Both Kohaku and Ruri are the spitting images of their ancestor, Lilian Weinberg.
- Innocent Blue Eyes: Kohaku has some pretty blue eyes. Seeing her for the first time, Tsukasa wondered if she by any chance was half-Japanese due to her eyes and blond hair.
- Knife Nut: Wields a pair of stone knives as weapons.
- Lightning Bruiser: Extremely quick in addition to her strength, according to Chrome, she's the only one in their village who is agile and strong.
- Love at First Sight: Subverted, says she's "fallen for" Senku after he rescues her, but later clarifies that she just likes people like him and wants to work together. So far she doesn't seem to be lying.
- Magic Skirt: As an agile action girl, she likes to jump and flip around. But as long as she is dressed, we never get to see her fujoshi; though it does show that she wears one when they are gathering iron sand from the river.
- Ms. Fanservice: While she doesn't fall prey to the usual fanservice for the sake of it, the camera loves her voluptuous body. In a couple of blink-and-you'll-miss-it moments, she even has her bare ass against glass for example.
- Muscles Are Meaningless: She's a slim girl of average height, yet she can easily take down huge, muscle-bound men like Magma and carry a huge vase full of water for several kilometers effortlessly. Senku and Chrome like to refer to her as a "gorilla" (which she, predictably, isn't very fond of).
- Not So Different: In the past her father tried to get her to become the new high priestess, but she refused because that was akin to saying "It's okay for Ruri to die because we have a replacement". After Chrome rejects one of Senku's plans for similar reasonsnote , Kohaku starts treating Chrome with more respect and even says she'd be happy if he married her sister.
- Surprisingly, with Tsukasa. They both became as strong as they are to save their sisters' lives. She even admitted it.
- Off-Model: She was wrongly given yellow eyes in the cover of chapter 17, despite the series clearly stating she has blue eyes.
- One of the Boys: Fitting her warrior status, most of her friends in the village are the male warriors. Funnily enough, despite her beauty and the fact that she looks exactly like her sister, Chrome has no interest in Kohaku romantically because she's apparently "more of a gorilla than a lady" (which earns him some knots on the head). Senku has given similar sentiments.
- Pervert Revenge Mode: Minister Ibara attempts to grab at her breasts while "inspecting" her for the Head's harem (which she's only joining in an attempt to rob the Head of his weapons), and he very nearly gets his thumb and arm snapped in half like a twig before being saved by Moz.
- She's Got Legs: And the artist seems to like showing them off.
- Shipper on Deck: After making sure that he doesn't just like her for her looks, Kohaku seems very happy at the idea of Chrome winning her sister Ruri's hand.
- Straight Man: When Senku gets all Mad Scientist, Gen spouts off "feather fluff" or Chrome becomes too passionate about his rock collection, she is the one who dryly reacts to it.
- Tomboyish Ponytail: She's a tomboyish Action Girl who's One of the Boys and wears her hair in a spiky ponytail, in contrast to her more feminine sister Ruri, who wears her hair lose.
- The Tease: She seems to get some amusement out of lightly flirting with Chrome and asking if he'd date her because of her resemblance to Ruri, which Chrome immediately points out is just silly talk before telling her to knock it off.
- Unsound Effect: Whenever she does something that demonstrates her physical strength (like grinding silica sand into a fine powder for glassmaking), it's accompanied by "Gorilla, Gorilla".
- The Worf Effect: She's usually the first person to get pressured in combat by the villains in order to show how powerful they are, falling into this against Tsukasa, Hyoga, Kirisame, and Moz. To Kohaku's credit though, unlike most instances of this trope, she rarely ever loses outright but is simply unable to stop them on her own.
- Worf Had the Flu: During "Round 2" with Kirisame (a friendly sparring match after Minister Ibara has been dealt with), they're equally matched. Kohaku denies holding back, saying that it would be disrespectful, and instead blames her performance last time on the long, awkward dress she was wearing at the time.
- Zero-Approval Gambit: She deliberately decided to become the "wild daughter" that her father would disapprove of and the other villagers wouldn't respect as much as Ruri, all to discourage them from thinking that Ruri was replaceable. She believed that Ruri would lose the will to live if she was no longer the priestess.
Voiced by: Gen Sato (Japanese), Matt Shipman (English), Jose Luis Piedra (Latin American Spanish)
A young villager regarded as a "Sorcerer", but his "sorcery" is the result of very primitive but meticulous research and experimentation on his surroundings. After meeting Senku, Chrome develops a respect for his superior and becomes his partner and assistant in matters of science. Chrome has a good heart and wants to cure his crush Ruri from the disease she's afflicted with, hence his research. However, Chrome is also an opportunistic braggart.
- Catchphrase: Frequently describes things he finds cool as "BAAAAD!" The Crunchyroll sub removes this, but the English dub keeps it.
- Collector of the Strange: While his "sorcerous" knowledge is immediately upstaged as soon as Senku arrives, Chrome has also amassed a large collection of various minerals and chemical components that Senku can immediately take advantage of.
- Commonality Connection: Senku regards him as a kindred spirit, as he is the Stone World equivalent of a scientist. Senku was going to teach him everything he knew too, as he believes he could be a worthy successor, but Chrome rejects the offer (albeit for reasons other than not wanting to learn science, which he does).
- Eureka Moment: He's prone to sudden flashes of inspiration, which has lead to him "inventing" some scientific advances completely on his own without any input from Senku. During the Treasure Island arc, he questions why he's one of the "Five Wise Generals" with four modern-day people, but Ryusui says that his unique experiences can offer important insights — and indeed, when Moz shows up in the cave, Chrome is the one who figures out that he's plotting against Minister Ibara, all because he knows from experience how hard it is to track someone.
- Everyone Can See It: It's extremely blatant obvious that he's in love with Ruri, but apparently he himself is completely unaware of it. Until Senku calls him out of it, and he realizes that he can no longer hide it.
- Hope Springs Eternal: In a very grand and philosophical sense. Senku points out that, as hard as people like Tsukasa may attempt to suppress or snuff out scientific advances, it is people like Chrome who prove that humanity's innate curiosity will always shine through, and result in the eventual development of technology and civilization of humanity, no matter how many generations or lifetimes it takes.
- Hot-Blooded: Extremely loud and passionate about science, even before he found out what his "sorcery" actually was. Every time one of his experiments produces an interesting reaction, he starts raving about how "BAAAAAAAAAAAAAD" it is.
- Idea Bulb: With the spin that it's linked to the current tech level of the story. Initially, his "bulb" is just two hands running electricity through a bamboo filament (based off of Senku's initial demonstration of electric light), but after they invent proper light bulbs he "evolves" into using those instead, and later on becomes a radar screen even when other characters are still using light bulbs.
- It's Been Done: A Running Gag for him. He comes up with many inventions/discoveries he thinks are revolutionarily new and original ideas, only for the pre-stone world characters to call him out for said subject to have already existed in their era.Chrome: So you do know what it is!? Damn it!
- Manly Tears: After Senku tells him about the technology and science of the previous world, Chrome is broken down to tears at the thought of all this progress being lost.
- Nightmare Fetishist: Downplayed. Like Kaseki, after he's depetrified in the Treasure Island arc, he immediately shouts how "BAAAAD" the petrification process was.
- Obfuscating Stupidity: When he's captured by Tsukasa's people and they start mocking him as a backward caveman, he resists the urge to display his actual scientific knowledge and instead plays dumb, acting like boiling seawater for salt is a major discovery. Which makes his subsequent escape by electrolyzing sweat into bleach all the more humiliating for Yo.
- Overshadowed by Awesome: In a sense, by Senku. For the standards of his time, Chrome is actually incredibly intelligent, and his endless curiosity has led him to self-discovery of varying scientific principles. However, Senku already has the pre-existing knowledge from modern society of said principles, as well as knowledge of how to build and create various modern devices and materials. When provided guidance from Senku though, Chrome has proven he has the intellectual capacity to understand and apply science in various crucial scenarios.
- Right for the Wrong Reasons: When he's captured by the Tsukasa Empire, Chrome remembers that Senku created the caustic sodium hydroxide by electrolyzing saltwater. He tries to create some to aid in his escape, but because he didn't partition his water container he instead creates sodium hypochlorite, more commonly known as bleach. It still helps him escape, however, since the bleach breaks down the ropes that held his bamboo prison together.
- Suspiciously Similar Substitute: With his strength and determination, he's essentially a smarter Taiju given those were the same qualities given to the latter boy.
- The Team Benefactor: Senku's Kingdom of Science wouldn't be able to accomplish nearly so much in such a short amount of time without the shed full of minerals that Chrome spent ten years accumulating. In this case, the benefactor works for the person he is benefacting.
- The Watson: Becomes this to Senku as someone whose self-taught "sorcery" gives him enough of an understanding to follow along, but still needs the more advanced principles and applications of science explained to him.
Voiced by: Tomoaki Maeno (Japanese), Josh Grelle (English)
One of the main fighters of the village. He serves as a guard and rigidly follows the laws of the village.
- Blatant Lies: He wasn't frightened by the bubbles. He was just confused by seeing something out of his range of knowledge. That's why his first reaction was to attack it.
- Foolish Sibling, Responsible Sibling: The responsible to Ginros foolish. Kinro is the one who has to ensure his brother is doing his share of the work in the first place.
- Good Is Not Nice: He may have a stick firmly implanted up his ass, but he's still a good person. When Kohaku says that she wants his help to save her sister's life, he immediately agrees.
- Handicapped Badass: Even with his "fuzzy eye disease", he was still skilled enough as a fighter to be the bridge guard and thus entrusted with the entire community's safety. He's even better at his job when this handicap is removed through wearing glasses.
- Hiding the Handicap: He has vision problems that wouldn't be an issue in modern society, but in the stone world they limit his fighting ability. He doesn't let anyone know, even after Senku designs glasses for Suika because he doesn't want to "make excuses" for his weakness. However, during his fight in the tournament, Sulka gives him her mask in order to fight at full potential.
- Honor Before Reason:
- He's the only one on the heroes' side who doesn't agree that saving Ruri is worth cheating in the tournament. It bites him in the ass when he asks Jasper whether or not Suika giving him her glasses counts as interference; the moment he turns his back, Magma jumps up and cracks him over the head, knocking him out cold.
- He also claims that a man doesn't make excuses for his shortcomings, adamantly refusing to tell anyone that he has "blurry eye disease" (nearsightedness) and demanding that Ginro not tell anyone either.
- Not So Above It All:
- In order to befriend him and enter the village, Senku coats his spear in a gold alloy, claiming it suits him as "Kinrou" means "gold wolf". Though he claims he won't be won over by such a ridiculous gift, he decides to keep it after briefly fantasizing about how badass his new spear looks.
- Further shown in an Out-of-Character Moment when he expresses the most emotion seen for him in the entire series when Kohaku forcefully takes his golden spear to make a lightning rod.
- Later on when the scientists begin automating their work, Ginro enthusiastically celebrates the fact that they'll never be asked to do that kind of back-breaking work ever again. Kinro celebrates too, but stoically.
- In order to befriend him and enter the village, Senku coats his spear in a gold alloy, claiming it suits him as "Kinrou" means "gold wolf". Though he claims he won't be won over by such a ridiculous gift, he decides to keep it after briefly fantasizing about how badass his new spear looks.
- Rugged Scar: He has a scar right under his left eye making him look more like a warrior and badass. It works
- The Stoic: Rarely changes expression, and remains firm in following the rules of the village.
- Stoic Spectacles: Senku eventually makes him some proper glasses to wear, and they make him look all the more stoic and serious.
- Those Two Guys: He is always with Ginro because they're always on guard duty together.
- Took a Level in Badass: Senku fixes his eyesight problems eventually with a pair of glasses, which naturally improves his performance in combat since he can clearly see what he's fighting.
Voiced by: Ayumu Murase (Japanese), Justin Briner (English)
A fighter and guard of the village. Unlike his older brother, Kinro, he is much more lax in his duties, and will try to get someone else to do his work if possible.
- Attractive Bent-Gender: Much to his horror, when forced into a dress and makeup he's cute enough to be immediately selected for the Head's harem, despite trying to show an unattractive personality. He was apparently a much easier pick than Kohaku.
- Big Damn Heroes: In Chapter 32, he manages to save Chrome from the sulfuric acid at the last second.
- Bishōnen: He's got some decently soft and feminine facial features and a somewhat slim body compared to other guys his age. This comes to bite him later when it turns out that these features combined with a little makeup and a dress result in him making a convincingly cute girl.
- Brutal Honesty: Unlike Kinro, he is openly sincere about being a coward.
- Butt-Monkey: Whenever there's some hilarious, general misfortune to be had, 9 times out of 10 Ginro is the unlucky victim.
- Changed My Mind, Kid: Initially refuses to return to the sulfuric acid spring, until he realizes that he can't live with himself if his friends get hurt because of his cowardice and rushes back just in time to save Chrome from falling in.
- Charles Atlas Superpower: Though he's not as strong as Kohaku or Kinro, Ginro too is much stronger than he looks.
- Dirty Coward:
- And damn proud of it. Turns out to be a Cowardly Lion in chapter 32 though, when he sets aside his fear to back up the less physically capable Senku and Chrome. After learning that Ruri will accept anyone who wins the Tournament, his "scum" part of his is unleashed to stop Senku and Chrome for winning the tournament, but is kicked in the nuts, much to everyone' joy.
- Made even more apparent when the Perseus sets sail. Ginro refuses to join the crew, terrified at the prospect of going on such a dangerous voyage. However, his scum part returns and he pretends to swim out after the ship in order to make all the girls who stayed behind believe that he's actually brave. However, that winds up backfiring badly.
- The "lion" part returns in full force as well though. Ginro wants very badly to escape, but finds that he simply cannot leave Kinro to the fate of petrification, and so he turns to work with Suika to free the mobile lab for Senku.
- Foolish Sibling, Responsible Sibling: The foolish to Kinros responsible. Ginro is the brother most likely to slack off or try and find the easiest way out.
- Harem Seeker: Briefly; he believes he can get a harem if he becomes chief, and promises the same for every man in the village. A girl bluntly points out that there aren't enough women for every man to get a harem, but he ignores her. Everyone in the village agrees they need to do whatever it takes to keep such an idiot from becoming chief.
- Hoist by His Own Petard: When the Kingdom of Science completes the Perseus, Ginro is amongst those selected to board it. However, he is adamant about not wanting to go on such a dangerous journey, and even has a panic attack until he's reminded that he has the option to refuse, which he does. However, upon the Perseus' departure, Ginro throws himself into the water and swims after it, calling out that he wants to go after all. It's revealed that it's all an act to look brave in front of all the girls who stayed behind and increase his stature with them. However, he's caught on Senku's radar, and brought on board by Taiju, resulting in Ginro being dragged into the very voyage he wanted to avoid.Ginro: Wow...Science is amazing...an amazing pain in the ass.
- Happens again when the Perseus sets off on the voyage to America. Ginro pretends his legs are weak and damaged to avoid going, only for Matsukaze, whose service Ginro encouraged due to looking like his old master, to carry him aboard the ship, all while proclaiming he will always carry Ginro whenever needed, effectively robbing Ginro of ever using physical-related excuses to get out of going anywhere dangerous.
- Impaled with Extreme Prejudice: He gets impaled from behind by Minister Ibara and he would have died from that if it weren't for Kohaku sacrificing herself by getting themselves petrified by the weapon thrown from Kirisame and so when Senku restores him, so will Ginro's life.
- Inexplicably Identical Individuals: Looks identical to Matsukaze's lord, which immediately earns him Matsukaze's complete loyalty.
- Peek-a-Bangs: To show that he's shy, but when Chrome almost died made him look pretty badass.
- Screw This, I'm Outta Here!: His "secret technique," is to run away from a fight and make it someone else's problem.
- The Slacker: Not very interested in his duties as a guard, especially noticeable in comparison to Kinro.
- Those Two Guys: With Kinro because they're always on guard duty together.. Kinro is the serious type, Not So Above It All type, while Ginro is the Dirty Coward of the duo.
Voiced by: Karin Takahashi (Japanese), Sarah Wiedenheft (English), Susana Moreno (Latin American Spanish)
A child wearing a watermelon mask who ends up one of Senku's allies.
- All of the Other Reindeer: Implied to be an outcast due to her behavior.
- Be the Ball: She can curl up completely inside her mask and roll around at high speed.
- Because You Were Nice to Me: Becomes loyal to Senku because he was the first person who didn't ask why Suika wears a melon on her head... not realizing that he wasn't respecting her privacy, he just doesn't care.
- Blind Without 'Em: Her vision starts blurring only about a foot from her face. Her Suika Cap makes this better, and then Senku converts it into glasses...
- Expressive Mask: The stem on her watermelon mask will sometimes move around when she's happy.
- The Faceless: Is mostly seen wearing her mask. Even when it's revealed what she really looks like, she still keeps wearing the mask after Senku puts lenses in it that allow her to see better.
- Gonk: While she's plenty cute underneath the watermelon mask, without it she tends to squint so hard to see that her entire face wrinkles up and she looks like an old woman.
- Little Stowaway: She sneaks aboard the Perseus, when it's launched, hiding inside during the trip to Treasure Island, before she's found out by Ryusui, who scolds her for it.
- Meganekko: The reason she wears her mask is because it focuses light so she can perceive the world better, as she is very near-sighted. Knowing this, Senku's able to make glasses using her mask as the frame.
- Odd Name Out: The villagers are generally named after gemstones, minerals and other elements. Then there's Suika, which literally means "Watermelon". Justified due to it being a nickname.
- Only Known by Their Nickname: "Suika" isn't her real name, just a nickname referring to the mask she wears. Despite this, it's the only name she's known by, and she even refers to herself in the third person by that name.
- Snooping Little Kid: Using her Suika cap as a disguise, she's able to easily listen in on conversations. She's also one of the more observant members of Team Science, shown by how she figured out that Kinrou needed glasses after only a few minutes watching his fight with Magma
- Stealth Expert: One of Suika's most distinguishing, and useful, traits is her ability to sneak just about anywhere. Whether it's snooping around the other members of Ishigami village to find out what desires Senku can tempt them with, locating Gen and smuggling him a knife in the midst of Hyoga's attack force, or searching for the captured Chrome amidst Tsukasa's stronghold, Suika's ability to slip in just about anywhere unnoticed is one of her most invaluable skills. It even allows her to stow away aboard the Perseus, after it's been launched, though she reveals herself to the rest of the crew once Senku goes ashore. After Ryusui saves her from being petrified, her stealth skills prompt Senku and the shore crew to instantly rate her as infinitely more valuable than Ginro, the sole other survivor.
- Tagalong Kid: Is the sole child to constantly join in on the other main character's activities and pursuits. Even more literally when she stows away on the Perseus on its first voyage to Treasure Island. To her credit though, she has proven to be incredibly helpful many times over, and has rarely if ever served as The Load.
- Third-Person Person: Since she's a little kid, she refers to herself in the third person as "Suika". However, the fact that "Suika" isn't her real name makes this a bit odd. Averted in the english dub where she refers to herself in the first person.
- Verbal Tic: She ends her sentences with "-da yo".
- The World Is Just Awesome: Gets a moment like this after Senku puts corrective lenses into her mask, allowing her to really see the world and people around her clearly for the first time. He even went to the effort of making sure that her first sight would be a beautiful field of sunflowers.
Voiced by: Monica Rial (English)A dog often found following around Suika.
Voiced by: Mugihito (Japanese) Kenny Green (English)
An elderly craftsman who gets drafted into helping Senku's group make glassware.
- Badass Beard: He has a rather impressively long white beard, and he's both absolutely ripped and an amazing blacksmith, capable of making almost anything Senku wants that involves construction or crafting, sometimes before Senku even asks him.
- Berserk Button: Exploited. Senku figures out that poor craftsman work really ticks him off, especially if it's done deliberately. And once he's sufficiently angry enough, he breaks out of his binds and shows how crafting is done. This is because Senku needed beakers and measuring cups to make Ruri's medicine.
- Big Ol' Eyebrows: His are thick and somewhat bushy, especially at the edges, to the point they cast constant shadows over his eyes.
- Black Bead Eyes: While in current times he has a case of Hidden Eyes, a flashback shows that when he was a child they were pure black like beads.
- Cool Old Guy:
- Offers Ginro some solid advice about not being ashamed of his fears, and "just happened" to have made an extra gas mask in case "someone" wanted to go help Senku and Chrome collect sulfuric acid.
- Once his creative fire is lit, he tears his way out of the ropes Chrome has him tied up with and reveals an extremely muscular build.
- Later, when Chrome comes up with an idea for a waterwheel and tells it to Kaseki, he goes Super Saiyan with excitement.
- During the ship-building arc, he enters one scene in Senku's automobile, wearing a very nice suit and looking to all the world like some kind of Dwarven pimp.
- Distinguishing Mark: Consciously averted. In Chapter 119, before he's de-petrified, Gen points out that a piece of stone is missing on his back. Since it's not a life-or-death thing the group is okay with it, and Suika remarks that it might even be something cool-looking. When it turns out to be shaped like a pile of poop, the group decides to hold off on reviving him until they get the missing piece back.
- Identical Grandson: In the Byakuya Spin-off manga, it's made abundantly clear that Yakov Nikitin is his ancestor. They share similar facial features and the same Running Gag.
- Instant Expert: He has such skill as a craftsman that he can craft suitable glass jars immediately after seeing molten glass for the first time (and watching Senku and Chrome fail miserably). He's also just as good as Senku in creating the gas masks.
- Intergenerational Friendship: With Senku and Chrome, over their mutual love of science and invention. At one point he laments the fact that he never had friends like them while growing up, but the two boys reply that age means nothing and affirm that they do consider Kaseki a friend, which makes him break down in Manly Tears.
- Nightmare Fetishist: Downplayed. When he's brought back after being petrified in the Treasure Island arc, he gushes about how fascinating it was being turned to stone, to the confusion and mild horror of those around him. According to Kaseki, he wasn't worried because he had absolute faith that Senku and the others would restore him; it also helps that the restoration process cured his "old man problems" like arthritis, making him feel better than ever.
- Old Master: Men like Kaseki exist in every era, experts that have devoted their lives to perfecting their skills.Kaseki: I've been a craftsman for fifty years, believe it or not. In fact, son, I'm kind of a big deal.
- Running Gag: His muscles bursting his clothes off whenever he gets fired up about building something.
- Token Adult: While most of the main cast are technically adults, or eventually reach legal adulthood (by modern standards) due to years progressing, Kaseki is the sole character who is not just a fully-grown adult, but an old senior at that, yet also partakes in many of the important events of the series, including both voyages of the Perseus.
- Ultimate Blacksmith: Stone age variant since he's spent almost his entire life in a pre-metalworking culture, but understands crafting techniques so well that just by watching Senku and Chrome fumble around with it, he's able to perfectly make a glass bottle on the first try. It is later played straight once Senku gets him access to a metal forge.
Voiced by: Reina Ueda (Japanese), Kristen McGuire (English)
Kohaku's older sister, and the shaman of her village.
- Accidental Marriage: Because Chrome passes out from the injuries he sustained fighting Magma, Senku (who was planning on throwing his match to Chrome) ends up winning the village games and marrying Ruri. However, thankfully, he also became the village chief as a result of his victory... giving him the right to divorce Ruri on the spot 3 minutes after "marrying" her. Ruri, naturally, was dumbfounded by the whole thing.
- Buxom Is Better: Ginro and Chrome certainly think so, when compared to her slightly less endowed sister.
- Dude Magnet: Chrome, Magma, Ginro, and Kinro all show interest in her at one point or another. The one she marries, Senku, is the only one who doesn't. That "marriage" lasts three minutes.
- Hartman Hips: Even shapelier than Kohaku's.
- High Priestess: Her role in the village is communion with the gods and the passing down of knowledge through the 100 Tales.
- Identical Granddaughter: Both Kohaku and Ruri are the spitting images of their ancestor, Lilian Weinberg.
- Ill Girl: At the start of the series, she is suffering from an unknown illness. It's 15-years long pneumonia.
- I Never Told You My Name: She knew Senku's full name all along because the 100 Tales were authored by his father Byakuya, and the 100th tale was a farewell message directed specifically at Senku.
- Strong Family Resemblance: Looks almost exactly like her younger sister◊, which Kohaku herself candidly points out when she jokingly asks if Chrome would fall in love with her next.
- The Storyteller: The villagers have learned some stories from the Pre-Stone World through her. Including a hilariously out of place Fist of the North Star parody.
- Tempting Fate: During the Village tournament, Ginro told Ruri that both he and Senku were planning to throw their matches since he knows that she really wants to get engaged to Chrome. Ruri, being the Nice Girl that she is, downplays her personal bias by saying that she is honestly okay with marrying anyone who wins the tournament. Ginro, being Ginro takes this as the go-ahead to betray the plan and try to win it all for himself.
- Tomboy and Girly Girl: With Kohaku, but due to the fact that she's really frail. After her pneumonia is cured, she goes for a run at full-speed, demonstrating that both sisters can be pretty rambunctious (though she's still far girlier than Kohaku).
Voiced by: Yasuhiro Mamiya (Japanese), J. Michael Tatum (English)
A strong, power-hungry man in Kohaku's village.
- Arc Villain: Of the Tournament Arc.
- The Berserker: His preferred method of fighting is charging through and attacking with brute force rather than coming up with any strategy.
- Blood Knight: Magma loves fighting and enjoys brutally beating others to a pulp.
- Boisterous Bruiser: He's an obnoxious and arrogant meathead who likes to throw his weight around.
- Character Development: As noted, he's the Arc Villain of the manga's first story arc, more than willing to kill anyone who gets in the way of his plans to become village chief (including a sick girl who probably won't last more than a year or two anyway). After getting humbled in the tournament and witnessing the amazing things science can create, he develops a grudging respect for Senku and puts more of a rein on his ambition. Tellingly, in Part 3 when Mantle suggests killing Senku, Magma looks angry for a second but then dismisses it by saying Senku is far too interesting a person to kill.
- Defeat Equals Friendship: Friendship is a big stretch, but he is at least willing to cooperate with and aid Senku, and has no immediate plans to kill him or any of the villagers, while still retaining ambitions to rule the village.
- Despotism Justifies the Means: Upon his introduction, it's fairly clear he couldn't care less about the village or well-being of its citizens, so long as he's the ruler. While he still wishes to rule the village even after his defeat, time will tell if this attitude continues to stick or not.
- Expy: A pretty transparent one of Gaston from Beauty and the Beast. The difference is that Magma is capable of changing, slightly.
- Dumb Muscle: Magma isn't very bright but he's still the strongest villager physically in Ishigami Village, which makes him perfect for jobs that require a lot of strength like mining ore.
- Hate Sink: At first. He's willing to kill anyone (including Ruri) and cheat in the Grand Bout in order to fulfill his ambitions to rule Ishigami Village, everyone else be damned. After his defeat, he loses this status somewhat.
- HeelFace Turn: Downplayed example. Though he continues to harbor his ambitions to someday rule over the village himself, the products of science that Senku and company bring to the village impress him enough that he's willing to cooperate to see what might come next. The threat to the village posed by Tsukasa's army helps too.
- Hidden Depths: Since the villagers are "people of the sea", he has a fairly good understanding of sailing and shipbuilding. During the competition at the start of the third story arc, his design is an outrigger boat that impresses even Senku and leaves Yo (who expected Magma's boat to be a half-assed canoe) with egg on his face.
- Hot-Blooded: Loud and confident in his abilities.
- Hypocritical Humor: When he, Chrome, and Gen are cornered by Ukyo, he proposes that Chrome absorb the arrows so they can find their assailant and take him down. When Chrome naturally refuses, Magma calls him selfish.
- Jerkass: Said out loud that he doesn't mind if Ruri dies, and that it would even be convenient for him if she did so as soon as possible just as long as he gets to marry her and become the village's chief first. He also shows no remorse from possibly killing Chrome in the Grand Bout, only planning to spare him if Ruri begged.
- Jerk with a Heart of Gold: Becomes this after his defeat. He cannot bring himself to kill Chrome or Senku when he has the chance, even saving Senku at first during their trip to the cave. He was also in on Gen's birthday plot.
- Jerk Jock: The strongest man in the village, and a complete tool. He gets a little better later on.
- Lantern Jaw of Justice: Has a prominent one, though he's anything but just.
- Leeroy Jenkins: In chapter 127 he steals the gun Senku made and proceeds to attempt to face off the entirety of Ibara's army with it, despite not having been trained to use it. Luckily Senku is quite good at Xanatos Speed Chess and figures out a way to use that to his advantage.
- Murder by Mistake: Very nearly does this to Gen. After seeing him perform a magic trick, he assumes that Gen is the "sorcerer" helping Kohaku and ambushes him. It's only averted because Gen was Properly Paranoid.
- Reformed, but Not Tamed: His personality and ambitions remain essentially the same even after becoming an ally.
- Sitcom Arch-Nemesis: Ends up in this dynamic with Yo after the two tribes merge.
- Token Evil Teammate: The first one to suggest that Murder Is the Best Solution. When he, Gen and Chrome come across a large number of petrified people Tsukasa is planning to revive and recruit for his army, Magma bluntly states they could simply smash the statues or hack off their limbs. Chrome and Gen then lampshade that Magma is similar to Tsukasa in this regard, and they're glad that he's on their side.Magma: Huh? What do I care about this buncha strangers?
- Took a Level in Kindness: After being defeated, he willingly cooperates with Senku for the good of the village, and even helps Gen in his plan to give Senku a surprise birthday gift.
A small, weaselly supporter of Magma.
- Blatant Lies: At the start of the tournament, he tries to take Kohaku out of the competition by claiming that he saw Suika drowning so that Kohaku will have to go rescue her. Everyone present points out how obvious a lie this is, even pointing out the flaw in his claim.
- Expy: Just as Magma is stand-in for Gaston from Beauty and the Beast, Mantle is clearly one for LeFou.
- Gonk: Has an extremely unflattering design, with a very deformed and weaselly face and extremely short stature.
- Lazy Bum: When Suika goes to check on him while he's guarding Homura's prison, he's nowhere to be found and she assumes he ran off to take a nap — again. Subverted when it turns out Yo beat him up and freed Homura, but then double subverted when flashbacks show that he was napping when Yo showed up.
- Sycophantic Servant: To Magma. Mantle's entire existence seems to revolve around serving Magma.
Voiced by: Jason Douglas (English)
Kohaku and Ruri's father and chief of the village. Often gets fed up with his younger daughter's antics.
- Adult Fear: He has to watch his oldest daughter suffer and struggle to breathe every day, knowing she'll probably die before she turns 20, and there's nothing he can do about it. Thankfully, that's when Senku enters the picture.
- It Was a Gift: He passed his shield (the one that helped him win the Grand Bout) onto Kohaku when she was a child...so naturally, when she casually says she has no attachment to it and turns it into a cog for one of Senku's machines, Kokuyo looks like she just ripped his heart out of his chest and stomped on it. The scene was Played for Laughs, though.
- Manly Tears: The sight of Ruri, finally cured of her pneumonia, causes him to fall to his hands and knees crying Tears of Joy.
- Parents as People: He does love his daughters, but as village chief he has to consider The Needs of the Many and make decisions that seem cold-hearted, like trying to find a new priestess so the Hundred Stories won't be lost.
- Reasonable Authority Figure: Ironically, he primarily demonstrates these traits after he steps down as village chief and hands the position to Senku.
- Retired Badass: He was a strong enough fighter to win the position of the village chief (and his wife's hand in marriage) during a previous Grand Bout. During the Stone War arc, he comes out of retirement and fights alongside the other villagers against Tsukasa's Empire of Might.
- Took a Level in Kindness: In the first arc he's highly distrustful of Senku and had hit the final straw on disowning Kohaku for disobedience before the story began. After the two of them manage to save Ruri's life he mellows out a good deal, accepting Senku as the right man to lead the village and gradually mending fences with Kohaku.
A nameless villager of Ishigami Village who is actually from another village overseas; he was sent away by his parents when he was a baby. He knows about the island that has the Soyuz spacecraft.
- Chekhov's Gunman: The nameless villager among the Ishigami Village ends up playing a major role in the hunt for the Soyuz spacecraft, and is named after it.
- Foreshadowing: Amaryllis instinctually charms Soyuz because she mistook him for the Island's leader.
- Hammer and Sickle: He possesses this tied to his belt.
- I Choose to Stay: In Chapter 140, Soyuz decides to stay on the Treasure Island in order to revive its population and take his rightful place as their leader.
- Moses in the Bulrushes: A fairly direct example, since he was the son of Treasure Island's rightful leader, sent away when Ibara staged his coup and took over, and was eventually discovered by residents of Ishigami Village and raised as one of their own.
- No Infantile Amnesia: It's revealed in chapter 134 that he will remember everything that he sees, even as an infant. Somewhat justified in that he was born to be this way, as before Minister Ibara took over, wives used to be selected on basis of their memory skills, rather than beauty.
- The Reveal
- Chapter 101 reveals that he is actually a descendant of the non-Petrified from the island outside of Ishigami Village, and that said island is inhabited with descendants of the astronauts who evacuated the International Space Station in their Soyuz spacecraft.
- Chapter 104 reveals that Soyuz remembered that when he was a baby, his mother was fleeing from a Petrification beam, leading to him drifting to Ishigami Village without his parents. This means there is a resistance against the ones who are using the Petrification in his home village!
- Odd Name Out: He's the only person from Ishigami Village whose name has absolutely nothing to do with earth sciencesnote ; when he reveals his name to Senku, he admits that he just went nameless for most of his life because his real name stood out.
- Photographic Memory: He possesses an incredible memory, recalling details as far back as his own infancy (which Kohaku and Gen rightly call impressive). In Chapter 117 when Ryusui is preparing to de-petrify Taiju, he realizes that the latter is missing one of his arms and they need to recover it first...but Soyuz already has the arm, having seen it when they were swimming to the villagers' location. In chapter 128, it's also how he knows that the island Head is his father despite his statue body broken into pieces by holding his hand from when he was a baby. And then in Chapter 134, we find out that his mother like her mother before her, was selected to become a wife due to her incredible memory.
- Walking Spoiler: When he's first introduced, we don't even know his name, and he doesn't do much until much later, where it's revealed that he's from another inhabited island.
Empire of Might
A group of de-petrified humans led by Tsukasa Shisho, who oppose Senku and his Kingdom of Science's efforts to restore civilization, along with its perceived corruption and flaws. Tsukasa himself handpicked young people with physical or athletic abilities that fit with his Darwinian vision and then revived them with the source of the de-petrification formula taken from Senku.
- Blood Knight: When it comes down to issues they are all too eager to settle things by fighting and showing off their strength.
- Defeat Means Friendship: Once Tsukasa makes a HeelFace Turn and Hyoga is defeated and imprisoned, the Empire of Might and all its members are absorbed into the Kingdom of Science. Hyoga and Homura also join the Kingdom of Science after the conclusion of the Treasure Island Arc.
- Dumb Muscle: Most are only present to pad out the numbers of Tsukasa's army.
- HeelFace Turn: Combined with Defeat Means Friendship. After being absorbed into the Kingdom of Science, all named members who did not already defect become new willing allies to Senku (essentially everyone but Hyoga and Homura). After the Treasure Island Arc, Hyoga and Homura also end up joining the Kingdom of Science.
- Might Makes Right: Their entire philosophy is based on strength alone and believes the weak are to be first to die.
- Younger Than They Look: Many have physiques resembling heavily-seasoned post-apocalyptic thugs from Fist of the North Star than typical teenagers and adolescents.
Voiced by: Yuuichi Nakamura (Japanese), Ian Sinclair (English), Arturo Cataño (Latin American Spanish)
- Adaptation Personality Change: A downplayed example. In the early manga chapters, he would participate in the comedy beats just like everyone else, getting stunned reaction faces whenever Taiju said something stupid. The anime removes this, which makes him look more serious overall despite still having the same dialogue and actions.
- Arc Villain: The first of the series. Upon his de-petrification, he makes himself the main obstacle Senku's goal of using science to rebuild the world and save every single human. Loses this spot to Hyoga in the final battle of the first saga shortly before nearly being killed by him.
- Anti-Villain: He genuinely believes in a better world, but his methods are both questionable and puts him in natural conflict with Senku.
- Arrow Catch: He easily catches the arrow from Senku's crossbow right out of the air, causing Senku to ramp up his efforts on producing a gun.
- Asskicking Equals Authority: After "killing" Senku (not really), he establishes himself as the leader of a new nation of his own creation.
- Ax-Crazy: He hides it very well but underneath his calm demeanor lies a very murderous individual who is hell-bent on proving his ideology to be right through extreme violence and even killing anyone who gets in his way.
- Back from the Dead: After the Kingdom of Science returns from Treasure Island with the Medusa device, they quickly put it to use on Tsukasa, who is still in cold sleep, petrifying and then reviving him, successfully healed of his fatal injury.
- Badass Baritone: Very powerful fighter with a deep voice to match in Japanese and English. Also overlaps with Evil Sounds Deep.
- Barbarian Long Hair: He has long, wild hair and is a force to be reckoned with.
- Benevolent Boss: As long as you're a young person and submit to the rules of his empire, he'll treat you right. In fact, he even remembers the names of all the random mooks who died from "Senku's poison gas attack" (in reality, Hyouga threw his man into a pit of naturally occurring poison just to see if they would really die) and individually buries each one of them.
- Blood Knight: Takes up the fighting job very easily and is quick to settle things by engaging in combat.
- The Bus Came Back: After being Put on a Bus due to being fatally injured by Hyoga and turned into a Human Popsicle to keep him alive, Tsukasa is finally brought back in Chapter 141 when Senku obtains the Medusa and uses it to heal him.
- Celebrity Survivor: Tsukasa was a famous martial artist known as "the strongest primate high-schooler" before the Stone World, with countless followers and fans. In fact, Taiju recognized him from TV when he first saw his statue.
- Charles Atlas Superpower: Capable of insane feats of strength such as fighting lions bare-handed, catching arrows, or even chopping a tree in half with one swing of his stone blade, all while being a teenager. It is unknown how he became so strong and it doesn't have anything to do with the petrification because he was known as "the strongest primate high-schooler" even before then.
- Chick Magnet: A quick flashback shows that he had legions of fangirls fawning over him during his time as a martial artist. It's currently unknown what he thought of it, although so far he doesn't seem to be too concerned about sex or romance (or even making friends with people, for that matter).
- Child Hater: Inverted, he's a teenager who hates adults.
- Creepy Shadowed Undereyes: They emphasize how dangerous he is.
- Death Glare: Gives Senku an incredibly intimidating one◊ when he rejects his offer to create a "pure world".
- Disproportionate Retribution: One adult beat him up for trespassing on his property and taking seashells, so he thinks all adults need to be wiped out.
- Does Not Like Shoes: It hasn't been brought up in-story yet, but he's clearly shown to not wear shoes. Given his character and ideology, it's probably to symbolize his closeness to earth and hatred of all things modern.
- Don't Make Me Destroy You: He respects Senku enough that he genuinely tried to give him a chance to swear off science so that he wouldn't have to kill him.
- Double Weapon: He takes to wielding a double-ended broadsword weapon after getting revived and joining the Kingdom of Science.
- Enemy Mine: After Hyoga's betrayal and near-successful murder of him, Tsukasa teams up with Senku to quickly defeat him.
- Establishing Character Moment: He's literally just been woken up from being encased in stone for over three thousand years as a last-ditch act of desperation by Senku and Taiju. Only his eye is visible, but he immediately asks what the situation is, and when Senku tells him, he blows the rest of the stone off his body like bullets before taking out several lions in an instant. Bare-handed. What an entrance.
- Even Evil Has Loved Ones: He really loved His little sister.
- Evil Luddite: He's so convinced that modern civilization was irredeemably corrupt that he's entirely willing to kill anyone who might possibly possibly restore it. He sends his soldiers to conquer Ishigami village just on the possibility that Senku had survived and might ally with them.
- Evil Red Head: Cover art reveals that his hair is a deep, blood-red color. Rather fitting.
- Fond Memories That Could Have Been: Before "killing" Senku after the latter refuses to give up science to spare his life, Tsukasa mentions that had they of met before the world turned to stone, he would've likely considered him his first friend. Some "what if" scenes then play out, where a young Tsukasa defends Senku's experiment from the three bullies. Later, he's seen bringing parts to help Senku build his rocket and another possibly happy moment where a doll of him went aboard the rocket with the Senku, Taiju, and Yuzuriha dolls. A brief scene also shows Tsukasa's younger sister with the seashell necklace that he had planned to make for her.
- Freudian Excuse: His mistreatment in the past is what caused him to develop his hatred of adults and then-current society.
- Friendless Background: Remarks that had he met Senku in the past, he would've been his first friend, and it likely would have changed his worldview for the better.
- Genius Bruiser: He's freakishly strong and a skilled fighter, but unlike Taiju he has intelligence to match, allowing him to keep up with Senku's schemes.
- Good Scars, Evil Scars: Compared to Senku, Taiju, and Yuzuriha, Tsukasa's body is covered in numerous scars, the most notable one stretching across his face and through his eye. This is subverted later on when he has a HeelFace Turn once Senku revives his sister.
- HeelFace Door-Slam: Once Senku manages to revive Mirai, Tsukasa is willing to abandon his ambitions and re-ally with Senku. However, it's at this point Hyoga makes his move, and Tsukasa ends up Taking the Bullet to save Mirai from him and is fatally wounded. He's shortly after made into a Human Popsicle until Senku can find a way to repetrify him so as to heal his wounds.
- Human Popsicle: Senku places Tsukasa in a cryogenic freeze in order to give him a chance of survival as he looks for the petrification method to heal his wounds.
- Tsukasa will happily rant about how scientific development will give rise to terrible weapons of war, and how science needs to be stopped, or at least hindered, to keep that from happening. Yet, between him and Senku, it is always Tsukasa who insists on bloodshed and killing as the only solutions to their problems. In contrast, many of Senku's scientific creations are born from his desire to subdue Tsukasa's army without killing anyone. Even creating gunpowder and dynamite are merely used to force Tsukasa into negotiations, rather than to actually kill anyone.
- Despite his hatred for adults and the corruption he accuses them of, he recruits Yo in his army. Yo is a police officer, an occupation that requires you to be an adult, and he was perfectly willing to abandon justice to serve him. Several more of his men look like adults.
- Several of the things Tsukasa claims to dislike about the old world and wants to stop happening such as wars, or people using their might and resources to push their will on others or claim things for their own - are all precisely things Tsukasa and his army indulge in.
- Just Like Robin Hood: Part of Tsukasa's desire to eliminate adults stems from his belief that they'll begin to impose taxes and bills on the weak and start profiting from them again. Unfortunately though, Tsukasa has taken to killing all of the adult statues he finds without concerning himself on whether or not they were rich or even bad people in the first place.
- Knight Templar: Is thoroughly convinced that he's the good guy and is simply doing what's necessary to create a pure, untainted world.
- Large and in Charge: He's so tall that Senku only reaches up to his◊ chest, and he quickly establishes himself as the king of the Stone World as soon as he thinks Senku is dead. It's eventually clarified that he's approximately 203.8 centimeters, or 6 feet and 8 inches tall, making him easily one of the tallest members of the cast.
- Lightning Bruiser: He's got all the speed, strength, and (presumably) endurance of Taiju, but with the fighting skills to put them to use against other people (and wild lions and sharks, for that matter). As Senku notes, in a world without guns, he's quite literally unstoppable. As a bonus, he's also a Genius Bruiser with enough knowledge of the natural world and strategic sense to keep up with Senku.
- Literally Shattered Lives: What he does to the petrified bodies of any older adult he comes across.
- Long-Haired Pretty Boy: He has this look going for him, although he has wilder hair and is far more intimidating than is usual for the trope.
- Meaningful Name: "Shishio" means "lion king", which is fitting since killing a lion is the first thing he does after waking up.
- Morality Pet: His little sister. In fact, Senku finding and awakening her was enough for Tsukasa to agree to abandon his ambitions and call off his mission to cull society.
- Mr. Fanservice: He's rather prone to the Female Gaze whenever he takes his shirt off (or, in the case of his very first appearance, is nude).
- Normal Fish in a Tiny Pond: Before the mass petrification incident, Tsukasa was very strong, but couldn't stand up against firearms. Now that he's in a world where weapons more advanced than a crossbow are rare, he's practically unstoppable.
- Not So Stoic: Every now and then, he does get visibly surprised; Taiju's and Yuzuriha enacting Senku's plan to fend off Tsukasa with a black powder explosion was even enough to warrant an Oh, Crap! from the latter. Likewise, Kohaku's strength had him a bit flustered (not enough to make him actually break a sweat, but enough to surprise him).
- Oh, Crap!:
- Ping-Pong Naïveté: Tsukasa shows a frightening amount of insight into Senku's actions and motivations. By the same token, he is amazingly blind to the personalities of his own followers. For example, he realizes that Senku survived their "final" encounter pretty much immediately, and generally manages to match wits with him, if not intelligence. However, despite Senku pointing out that he was in this to save everyone indiscriminately, he blindly believes Hyoga's story that Senku used poison gas to kill his men (Hyoga actually killed them to test the lethality of a gas cloud). He seems to assume that everyone who's on his side both agrees with him and shares his morals, and doesn't question them.
- This bites him in the ass when Hyoga betrays him. As it turned out all Hyoga needed to do was keep his mouth shut about his actual goals to get in a position close enough and wait for an opportunity to usurp Tsukasa, who wholeheartedly trusted him in spite of not really knowing Hyoga.
- Put on a Bus: The conclusion of his saga as the Big Bad sees him fatally wounded by Hyoga after his HeelFace Turn and needing to be put on ice while Senku and the others set out to find out how to cure him via petrification.
- The Rival: Towards Senku, due to their opposing desires for the new world.
- Science Is Bad: Beyond his hatred of adults, he also hates modern society in general, seeing the Stone World as a paradise untainted by people who want to control land for themselves. He's essentially the opposite of Senku, who was actually first alerted to Tsukasa's dangerous nature when he mentioned ominously that "he just realized he (Senku) could probably recreate modern civilization from scratch".
- Soft-Spoken Sadist: Tsukasa rarely raises his voice, typically only speaking with a soft, even tone- even when he's threatening to kill people. It's rather... unsettling.
- The Spock: Tsukasa shows very little emotion beyond Tranquil Fury and annoyance. Being rather intelligent as well, he even takes a book straight from Spock's page at one point when he chastises Taiju for "failing to see the logic in his resolve". note
- Strong and Skilled: He has freakish Super Strength, but his combat prowess is backed by impressive martial arts talent.
- Super Strength: Strong enough to kill a lion with a single punch and crush rock with his bare hands.
- Taking the Bullet: When Hyoga betrays him, he ends up impaled on Hyoga's spear to take a blow that would have otherwise killed Tsukasa's little sister.
- Tranquil Fury: Tsukasa never openly rages or rants when he's angry; rather, he just gives off a frighteningly intense Death Glare towards whoever crossed him. It's enough to unsettle even Senku.
- The Unfettered: He points out that, while Senku may claim to be The Spock, he still has people that he cares about who's lives can be used as a threat against him (in this context, Taiju and Yuzuriha). Tsukasa, meanwhile, despite having hundreds of followers and fans note has nobody that he actually truly cares about. This is why Tsukasa ultimately believes he's destined to win over Senku. Ironically, he turns out to be correct in a way, but its Tsukasa himself who gets bit in the ass by this; immediately after his long-thought dead little sister is brought back to life, Hyoga uses her life against him in exactly this manner.
- Verbal Tic: He uses an affirmative "Mmm" (equivalent to saying "Yes") at the start of most of his sentences.
- Villain Respect: Tsukasa might have tried to kill Senku, he might be perfectly willing to kill Taiju if the latter ever goes into a rage and tries to attack him, and he might be dismissive of Yuzuriha as a woman in a world without science, but it's fairly obvious that he respects the first two at the least, and he allows Taiju and Yuzuriha into his kingdom without fuss, even if he keeps an eye on them to make sure they're not helping Senku.
- Villain Team-Up: He teams up with Lily in the Last Cloudia crossover campaign Tsukasa Shishio's Challenge to take out several monsters in hopes of getting back to his home world. He doesn't trust her however which is something she picks up. The distrust comes to a head when she unleashes monsters on two children.
- Visionary Villain: His goal of building a stone age society in harmony with nature and free of the corruption that plagued the modern era is certainly ambitious, and he's put a lot of thought into how to go about it. To that end, he's gathered the statues of dozens (if not hundreds) of people who he believes can play a part in bringing his vision to life.
- Well-Intentioned Extremist: Wants to take advantage of the new world by shaping it into a more peaceful one. Unfortunately this includes destroying the statues of adults who ruined the world and halting the advance of science.
- World's Strongest Man: Prior to the Stone World, he was known as "the strongest primate high-schooler". In a world without guns or explosives, Tsukasa is a One-Man Army.
- Younger Than They Look: Tsukasa is still high-school aged (presumably around 17-19), but his height and musculature make him look quite a bit older. Somewhat ironic considering his hatred of adults.
Voiced by: Akira Ishida (Japanese) Jerry Jewell (English)
One of Tsukasa's lead generals, who makes his presence known when the Stone War Arc begins.
- Arc Villain: Takes over as the main threat at the conclusion of the Stone Wars arc, as it turns out he was simply trying to usurp Tsukasa from under him. Ends up very short-lived though, as he is quickly defeated by Tsukasa and Senku teaming up at the last minute.
- Bad Boss: Unlike Tsukasa, he gives no value towards the lives of his subordinates, killing them on a whim freely and then lying to the former about it. It sets up his true nature as The Starscream, as it's our first glimpse at just how different he is from Tsukasa.
- Bastard Understudy: He never actually shared Tsukasa's luddite views and only sided with him so he could eventually take his throne. When Tsukasa made a HeelFace Turn, he immediately dispose of him.
- Batman Gambit: Knowing that Tsukasa is too strong to overthrow directly, he plays the part of a loyal subordinate until Mirai is awakened. He then attacks Mirai, knowing that Tsukasa would throw himself in front of Hyoga's spear to protect her.
- Blade on a Stick: His weapon of choice is a long spear. Specifically a pipe-spear, or Kuda Yari, as it is known in Japanese. Both it and the style he uses, Owari Kan Ryu, are real.
- Came Back Strong: Sort of. When revived and joining Senku's Science Kingdom, his pipe-spear is upgraded with Senku's technology. Specifically, the spear's tip is now metal and the tube itself has been carbon lubricated, allowing Hyoga to spin and thrust the spear even faster than before, due to the further reduced friction.
- Catchphrase: He likes to say when or not things are "done properly", almost to the point of being a Verbal Tic. He also tends to insult people as "mush-for-brains".
- Crazy-Prepared: Hyoga himself is well aware just how dependent he is on his specialized weapon. As such, at the climactic battle for the cave of miracles, he has a spare standing by, just in case one of his opponents tries to trap his weapon. He's also heavily prepared for his plan to ultimately betray and kill Tsukasa, having already scouted out the river he knocked Tsukasa and Senku into, allowing him to know where they would wash up, so that he could deal with them without interference...which seems to imply that he was even aware of where Mirai Shishio was buried, as the point he knocked Tsukasa and Senku in was very close to where she was found and revived, mainly because it was around her that he figured he had his best chance of breaking through Tsukasa's guard.
- The Dragon: Seems to be this for Tsukasa. Is later revealed to be Co-Dragons with Ukyo, though Hyoga still seems to have more pull between the two of them.
- Dragon Their Feet: A version that combines with The Starscream. After Tsukasa accepts a ceasefire with the Kingdom of Science in return for his sister's de-petrification, Hyoga springs into action, attempting to kill both Tsukasa and Senku and take over the Empire of Might.
- Even Evil Has Standards: After being revived and released, he has to make a choice on who to side with. He immediately acknowledges that him siding with Moz would mean death for Gin, Nikki and the rest of Senku's crew, since they have no other good fighters on their side. As cold and ruthless as he seems to be, he is not completely OK with this, mainly because he happens to have Villain Respect for Senku and his crew. That being said, it took Moz showing him that he is an untrustworthy Harem Seeker to fully convince him to lend his strength to Senku.
- Eviler Than Thou: Whereas Tsukasa seeks to create an allegedly peaceful and egalitarian society by suppressing science and avoid de-petrifying old folk with vested interests from the old world, Hyoga desires to go further and establish a Social Darwinist society where only the strong or "those that excel" are allowed to live.
- Everything's Better with Spinning: His fighting style involves twisting his spear in such a way that the tip moves in a circular rotation, making it nearly impossible to block. This is accomplished by sliding it through a pipe as he thrusts, while rotating the shaft with his thrusting hand. The spin uses the pipe as a fulcrum to exaggerate the motion of the spear's head along the extended shaft to make its movements much less predictable. This plus the pipe handle, which allows him to slide the spear back and forth incredibly fast without the friction of his own hand holding it, makes his weapon amazingly deadly.
- Eyes Always Shut: His eyes have always been shut in every scene he's in. Ironically, one of the first things he says is to notice Kinro's bad eyesight.
- Faux Affably Evil: Speaks in a polite tone, yet is total bad news.
- Good Feels Good: During the climax of the Treasure Island arc, he catches himself putting his trust on Senku and his crew in order to get his proper weapon back and defeat Moz. And lo and behold it turns out his trust isn't missplaced.
- Good Scars, Evil Scars: In contrast with the small, relatively ignorable scars characters like Senku, Gen, or even Tsukasa have, Hyoga sports a huge pattern of five circles covering his entire lower face that he hides under his turtleneck. When he sides with the Kingdom of Science during Chapter 130 by attacking Mozu, he pulls down his facemask to reveal that his scars are gone, having been removed by his second de-petrification.
- Hero Killer: Comes inches away from killing Kohaku, and only fails because Gen and Suika sabotaged his weapon. He also stabs Kinro, which would have been fatal had it not been for Senku's medical knowledge.
- Knight of Cerebus: Once he makes his entrance, things quickly become much more serious.
- Lack of Empathy: When Tsukasa mentions the lives lost in the poison attack, he doesn't know who Tsukasa is even talking about; it's the warriors that where with him that he made fall into the poison to see if it was real. He gravely wounds Tsukasa just seconds after the man sees his little sister alive for the first time in thousands of years, skipping no beats in taking his throne from him.
- Lean and Mean: He's got a lean, wiry build, but he's easily many times stronger than Tsukasa's army of muscle-heads; moments after being awoken for the first time in thousands of years, Hyoga easily defeats/kills 10 of them at once by himself.
- Mysterious Past: Out of all the people released from the petrification, we know nothing about who he was before it happened. All we know for certain is Tsukasa knew about him in the past and had actively searched for him to be his right-hand man. We do see him as a child training in the Owari Kan Ryu style of spear-fighting however.
- Not So Different: In Chapter 132, he mentally compares the lifetime of effort and dedication it took him to learn his spear-fighting style to Senku's lifetime of dedication to science, and as a result begins to respect science after seemingly hating it in his last appearance.
- Oh, Crap!: His normally cool and calm expression changes to a terrified one, when he realizes that Moz is actually a much more skilled fighter than what he gave him credit for.
- Social Darwinist: The difference between his ideology and Tsukasa's is that while both believe that the petrification offers them an opportunity to reboot society, Hyoga believes that only exceptional people should be restored while ordinary people are purged. When he's revived in Chapter 130, he's softened his stance just a little, seemingly being okay with leaving the "ordinary" people as statues rather than actively trying to destroy them.
- The Starscream: He was only Tsukasa's underling so he could have a chance at killing him one day.
- Villain Respect: When he's revived during the climax of the Treasure Island arc, Hyoga admits to himself that even though he disagrees with them, he respects members of the Kingdom of Science because they do things "properly". He even laments the fact that he and Senku have opposing goals.
- We Can Rule Together: He makes this offer to Senku at the end of the Stone War, and makes it clear that he's willing to torture Senku into accepting it.
- We Have Reserves: Sends his grunts to attack Ishigami village under the logic that even if the foot-soldiers all die, it will provide him with valuable intel on whatever defenses Senku has set up. Soon afterward, he knocks them into a cloud of invisible gas to confirm that it's lethal.
- Worf Had the Flu: Or rather lost his preferred weapon. Turns out the reason he couldn't best Moz was because the weapon he was given was a simple spear, without the original's Everything's Better with Spinning features that allowed his fighting style to be so deadly. Once Senku and Co. manage to properly adjust the spear, Hyoga easily wipes the floor with Moz.
Voiced by: Aki Toyosaki (Japanese), Megan Shipman (English)
A young woman in Tsukasa's army. She serves as Hyoga's right hand and acts as a spy/scout outside of combat, keeping an eye on Ishigami village from the trees.
- Beauty Is Never Tarnished: Her scar is located on her thigh rather than her face.
- Chekhov's Gunman: After being quickly captured and imprisoned by the Kingdom of Science, she remains imprisoned in Ishigami Village. Several chapters later, she is released from jail by an unwitting Yo, and rushes to aid Hyoga in his coup against Tsukasa, mainly by blowing up the Cave of Miracles that produces the de-petrification formula.
- Dark Action Girl: Appears to be Tsukasa's very own version of Kohaku; one of the first things she does is prove her worth by nearly burning down the whole village. The jury's still out on whether or not she's really all that bad though; Senku seems to believe that they can convert her to his side with the allure of creature comforts that science can create.
- Kill It with Fire: Causes more damage to Ishigami Village than the rest of Hyoga's invasion force combined thanks to her talent for creating and applying fire.
- Meaningful Name: Homura means "flame".
- Undying Loyalty: A villainous version. Her loyalty is to Hyoga, not Tsukasa or his cause. Thus, she is the only one to outright aid Hyoga in his attempted coup against Tsukasa. When it fails and the two are imprisoned, she is content that she at least gets to remain by Hyoga's side.
- Weak, but Skilled: She isn't much stronger than Senku, but has gymnastics training which allows her to make the absolute most out of her body's movements.
Niki "Nikki" Hanada
Voiced by: Atsumi Tanezaki (Japanese)
A sentry in Tsukasa's army. Upon discovering Senku's telephone, she tries to destroy it, until the voice of her favorite singer sways her to turn.
- Affectionate Nickname: Back in her Judo club days, the underclassmen would call her "Nikki" or "Boss"; the former is what most of the characters in the Stone World call her.
- Boobs of Steel: Has the biggest bust in the series — even bigger than Ruri and Minami — so, naturally, she's also the physically strongest girl. She's even able to bruise up the likes of Taiju with her punches.
- Brawn Hilda: Downplayed. While her figure is definitely 'Amazonian' and she's not exactly ugly either, Nikki is drawn with a lot of muscular bulk, has a rough personality, and isn't styled to be as beautiful as other prominent female characters. Her character design gets some changes around the Treasure Island arc, where she's drawn with slimmer muscles and larger eyes, veering her closer to Amazonian Beauty.
- Bruiser with a Soft Center: A tall, brawny former Judo-ka who describes herself as "tough as leather", but loved Lillian Weinberg's pop music and has very cute and girly handwriting.
- Cleavage Window: Her outfit in the Treasure Island arc is form fitting with extremely deep cleavage showing off her massive breasts, and forms a window with the scarf she wears as a collar.
- Dark and Troubled Past: Strongly implied, as she says that Lilian's music "saved" her, and flashbacks to her childhood show her with bruises and bandages on her face. However, this hasn't been explored past her introductory arc.
- Early-Bird Cameo: She appears in a Flashback in Episode 16, when people around the world are watching Lillian sing on the International Space Station.
- Fangirl: Of Lilian Weinberg, who she listened to during her student days to the point it "saved her". She even knows her exact record sales and three measurements.
- Gainaxing: During the latter portion of the Treasure Island arc, her large breasts jiggle intensely during action scenes due to how deep her outfit's cleavage is.
- HeelFace Turn: She was firmly on Tsukasa's side until she heard Lilian's voice on the last record on Earth. She swears to protect it by joining Senku's side.
- Non-Standard Character Design: Minor, but she starts out noticeably lacking the "doe eyed" look of some of the other female characters (Kohaku, Ruri, etc) and has more pronounced lips. As mentioned above, she does start getting drawn more in line with the other women in the series later on.
- Spotting the Thread: While Senku is able to accurately calculate Lilian's measurements based on a picture of her, those aren't her publicized measurements, which a fangirl like Nikki knows by heart. When Gen tries to claim that they're her real measurements, Nikki responds that a consumate professional like Lillian would never drop the facadé in front of a fan.
Voiced by: Kensho Ono (Japanese)
One of Tsukasa's direct subordinates. Formerly a submarine sonar operator, he has an extraordinarily sharp sense of hearing.
- Anti-Villain: He's Tsukasa's right-hand man, but quickly demonstrates that he's an affable fellow with a strong sense of fair play. And then it turns out that he's not a villain at all, and willingly joins Senku's side because he wants the bloodshed to end.
- Archer Archetype: Archer hat? Check. Robin Hood-esque clothes? Check. Slim, almost weak-looking body? Check. Deadly precision with a bow and arrow? Check. Yep! He's an archer.
- Co-Dragons: With Hyoga; Yo even refers to Tsukasa, Hyoga, and Ukyo as the "Big Three". However, it appears that Hyoga has a little more authority than Ukyo.
- Cunning Linguist: Speaks both English and Japanese and takes advantage of this to speak to Gen and Senku (both of whom, of course, also know English) without anybody understanding them.
- Early-Bird Cameo: He makes an unvoiced appearance in Episode 10 of the anime, about 40 chapters before his formal introduction in the manga.
- Giving Up on Logic: Ukyo serves as the dealer in Senku and Ryusui's cheating-heavy poker game in Chapter 144; when the game ends with five Aces on the table, he metaphorically throws his hands in the air and says "Whatever..."
- HeelFace Turn: He becomes a full-fledged ally after Senku accomplishes beating Tsukasa's army without killing anyone.
- Hidden Agenda Villain: Despite having high standing in Tsukasa's army, he lies to Tsukasa about where he captured Chrome, keeping the existence of the hidden telephone a secret for some unknown reason. As it turns out, he's actually averse to violence and is trying to to keep Senku's group around in order to "test them out" and see if they'd be willing to stop Tsukasa's army without killing anyone.
- Improbable Aiming Skills: Shoots many arrows at Chrome, taking care to just barely miss each time. This while he's on the move to shoot from multiple angles and, thanks to a smokescreen obscuring his view, detecting Chrome solely through hearing. His most impressive show of marksmanship, however, has to be when he catches Chrome with an arrow in mid-free fall from a cliff.
- Nice Hat: He's never seen without his trademark cap. He loses it during the Treasure Island arc when Ibara takes the clothing from the petrified Perseus crew, so Suika makes him a copy out of paper.
- Older Than They Look: Implied. He's at the very least old enough to have been a highly experienced sonar technician even before the Stone Age, but he looks like he could pass for about 14 years old.
- Ridiculously Average Guy: He's reasonably intelligent and has exceptional hearing, but other than that he lacks any major quirks or personality defects, meaning he's probably the most "normal" character in the whole series. As such he typically plays The Watson in serious moments and the Only Sane Man in comedy beats.
- Super Senses: Has an incredible sense of hearing courtesy of working with sonar equipment for submarines before the Stone Age. His eyesight is also clearly nothing to scoff at either, considering his Improbable Aiming Skills with his bow and arrow.
- Technical Pacifist: He doesn't like violence nor watching people die, preferring to use his arrows to corner his opponents and capture them despite his excellent aim. However, it's implied by his position in Tsukasa's army and capture of Chrome that he'd ultimately be willing to kill if he had to.
Voiced by: Yoshiki Nakajima (Japanese)
A former policeman recruited into Tsukasa's Empire of Might. While Chrome is captured, he's in charge of guarding the prisoner and setting up the traps to foil Senku's rescue plan.
- All Men Are Perverts: Is usually apart of the "drooling" crew alongside Ginro and Moz whenever a pretty girl comes around. He's very unlikely to successfully get with any of the women he tries to impress, however.
- Benevolent Boss: Yo is stern towards his subordinates, but does care about them. When one of them accidentally exposes one of the pit traps around the prison cells, Yo's punishment is a single Megaton Punch, but then immediately afterwards he says the matter is settled and tells the man not to dwell on it. When Chrome manages to escape, he takes the blame entirely upon himself, telling his subordinates to claim that he died chasing Chrome so Tsukasa and Hyoga won't punish them any further.
- Blatant Lies: After the Empire of Might falls, he tries to get into the Kingdom of Science's good graces by claiming that he suffered amnesia and doesn't remember anything he did before. Nobody buys it for a second, and he even admits to his "sins" when he thinks that helping Yuzuriha fix the broken statues will win him brownie points.
- Butt-Monkey: Up there with Ginro and Magma when it comes to being the butt of the joke and generally unfortunate. However, he generally brings it upon himself with his overconfidence, and he gets to genuinely shine sometimes when he gets out of his own way. Occasionally.
- Eyepatch of Power: He still has a patch of stone covering his right eye that gives him this look, though he later pulls it off and gives it to his subordinates to use as evidence of his death. Becomes part of a Running Gag where every time he gets surprised, his eyes would pop out and destroy the eyepatch.
- Faking the Dead: After Chrome escapes, rather than face whatever punishment Hyoga and Tsukasa would dole out for his failure, he has his subordinates tell them that he died trying to recapture Chrome.
- The Gunslinger: After Senku creates a primitive revolver, this becomes Yo's designated role, given his previous experience with firearms from being a police officer.
- Improbable Aiming Skills: Parodied. When he tries out Senku's primitive gun, he misses all the bottles but hits a poisonous snake that nobody saw. Everyone praises him, but he thinks to himself "I really was aiming for the bottles... I need practice". Played straight in chapter 131, where he manages to shoot Minister Ibara's hand and make him drop the petrification weapon.
- Lawman Baton: His weapon of choice in the stone world.
- Not Me This Time: A comedic version. As mentioned, he develops a pseudo-rivalry with Magma centered mostly on his making fun of "the savages" for not knowing about modern science. In Chapter 87 when Senku declares that humans are going to fly, Magma starts to laugh it off but immediately suspects Yo is going to mock him...but Yo openly admits "Yeah, I'm not laughing this time, I have no idea what he's talking about either."
- Rabid Cop: In a flashback, he's shown being very flippant about shooting a suspect who was running away.
- Screw This, I'm Out of Here!: Cuts his losses and runs for the hills when Chrome escapes his prison under his watch, not wanting to be killed by Tsukasa or Hyoga.
- Sitcom Arch-Nemesis: Ends up in this dynamic with Magma after the two tribes merge.
- Smug Snake: He thinks he's on the same level as Tsukasa, Hyoga and Ukyo, but he's little more than a stupid, violent thug. At one point, Gen sets up a boat-designing competition to determine the vessel they'll use to sail to South America. His entry is a shoddily-made raft that wouldn't be considered sea-worthy under ANY circumstances.
- Stab the Scorpion: In Chapter 124, several members of the cast are extremely leery of entrusting him with Senku's newly-invented firearm. Then, when they line up some bottles for him to shoot, he misses completely...and a highly venomous (and now dead) snake falls from the ceiling, earning the others' respect. In the last panel of the chapter, Yo nervously thinks to himself that he WAS aiming at the bottles, and that he's going to have to get very good very fast in order to maintain their respect.
- Taking the Heat: Tells his subordinates that, once they report his death, they should place all the blame for Chrome escaping on him to avoid being punished themselves.
Voiced by: Yōko Hikasa (Japanese), Kristi Rothrock (English)
Formerly a reporter, Tsukasa utilized her skills to decide who to revive.
- Does Not Like Shoes: She tends to go barefoot.
- Early-Bird Cameo: She gets a voiced appearance in episode 19, which takes place long before she was officially introduced in the manga.
- Hidden Depths: She initially comes off as a shallow Tsukasa fangirl, but over time it's revealed that she was quite passionate about her work. She breaks down crying Tears of Joy when Senku builds her a camera (or at least a daguerreotype), and she's the one most affected when the Perseus departs because she knows everyone personally and is worried that they might not make it back alive.
- Hot Scoop: She was a reporter with extensive knowledge of important people throughout Japan, and she's the most full-figured woman in the show's cast.
- Male Gaze: You could make a drinking game out of how much her rear gets shown every time she's in the spotlight. Pretty much every appearance she makes will have her body shown off one way or another.
- Meaningful Name: Her name translates to North-East West-South - in other words, NEWS.
- Ms. Fanservice: Definitely gives Kohaku a run for her money when it comes to how much the camera loves her. Senku outright describes her as a "Marilyn Monroe type".
Tsukasa's younger sister. She had been rendered brain-dead prior to petrification, leading Tsukasa to become a prized fighter to pay for her life support. After winning the Stone War, Senku uses the de-petrification formula to free her and bring her back to full health.
- Back from the Dead: Played with. Mirai wasn't "dead" before the petrification, but she was clinically brain-dead, meaning she was Only Mostly Dead. The only reason she's alive now is due to the healing properties of the petrification, meaning once Senku freed her, her brain was completely healed and she was effectively revived.
- Early-Bird Cameo: First appears in Chapter 11 as the little girl walking home from school with Tsukasa in Senku's What If? scenario where Tsukasa had been childhood friends with him alongside Tajiu and Yuzuriha. She is properly introduced in Chapter 79, when she is revived to full health.
- Ill Girl: Was deathly ill in the past.
- Younger Than They Look: She went into a coma at age six, then was petrified with the rest of the world six years later, meaning that she looks twice as old as she is mentally. Thanks to the relative harshness of the Stone World, as well as having to watch over her brother's body in cryo-stasis, she had to mature quite quickly — but thankfully she has plenty of friends around to help.
A multinational team of six astronauts and cosmonauts, who were spared from petrification due to being aboard the International Space Station at the time of the event. They subsequently returned to Earth in a pair of Soyuz spacecraft, living out their final days on a secluded island.
- Adam and Eve Plot: There were only six people aboard the International Space Station during the stone incident- three men and three women- so they presumably got to repopulating the planet after they landed from space. It would definitely appear that way at least, as both Senku and Tsukasa point out that Kohaku appears to have foreign blood in her despite being in Japan... and sure enough, at least four of the astronauts appeared to have been Caucasian.
- Hero of Another Story: As noted above, they were seemingly the only six humans not affected by the "Petrification Beam" and began the process of repopulating the planet and building a foundation that could hopefully be used to restore the petrified people. The short spin-off Dr. Stone reboot: Byakuya actually is their "Another Story".
- Multinational Team: The group consists of three Russians, a Japanese, a Chinese-American and a Caucasian American from the South.
- Posthumous Character: Having not been turned to stone, they're all obviously long-dead by the time the series picks up nearly 4,000 years in the future. More specifically, chapter 45 reveals that most of the astronauts were eventually killed by Pneumonia.
- Strong Family Resemblance: Some of the villagers more closely resemble their distant ancestors than others.
Voiced by: Keiji Fujiwara (Japanese), Kent Williams (English)
- Adaptational Dye Job: His hair color isn't entirely consistent in illustrations, but Senku and Byakuya tend to share the same hair color. In the anime, Senku is blond with green tints while Byakuya's hair is entirely white.
- Celebrity Survivor: As an astronaut, he was popular and well-known enough in Japan for the kids in Senku's class to instantly recognize him just by hearing his name.
- Chick Magnet: The girls in Senku's class and the reporter doing the live coverage on the day of the launch were all smitten with him. He eventually got together with Lilian and had children with her upon landing back on Earth, as well.
- Determinator: Byakuya spend his entire life after returning to Earth preparing it for Senku's return. Just leaving the stories and clues for Senku and believing he would be there in the future to make use of them would qualify Byakuya for this trope, but in Chapter 115, we see that he literally spent the rest of his life gathering rare metals that would help Senku in the future, finally dying of old age while panning for gold in a river. And his efforts paid major dividends, as he was able to collect an astonishing amount of platinum from that single river.
- Fling a Light into the Future: He came up with the 100 stories of Ishigami village, both as a way to teach future generations about how to survive and to ensure that Senku would have allies to help him rebuild the world. He also made sure he was buried with a time capsule containing a record that plays out a message for Senku and a song for the villagers in case Senku couldn't convince them to help him restore humanity.
- Later, we find out that Byakuya also spent the last decades of his life gathering rare materials for Senku, literally working until he collapsed into the river and couldn't get back up. Said materials provided Senku with a way to manufacture the revival formula at a rapid pace. Byakuya is a contender for patron saint of light-flinging.
- Good Parents: He and Senku had a pretty healthy father-son relationship, Byakuya selling his car to buy Senku a lab in order to foster his early interest in science, and including a farewell message in the 100 Stories. He also quite literally works himself to death gathering materials for Senku in the future.
- Meaningful Name: His surname means stone-god. In fact, it's even more appropriate for Byakuya than Senku, as Byakuya was quite literally the first leader of the Stone World.
- The Reveal:
- Byakuya is Senku's father and the founder of the village, and he even passed on legends about Senku himself down the royal line. This is why Ruri knew Senku's surname before he even told her.
- However, it's also revealed shortly thereafter that he and Senku are not blood related.
- Shared Family Quirks: Like Senku, he was a bit of a Troll; the first thing he does when he goes to space is convince Lilian to act like a diva just to annoy everybody, and then he teases her by playing her music on the station against her wishes.
- Neither of them cares much for ceremony either; his recorded message to Senku starts off sounding completely serious before he cracks up and says that this mushy stuff isn't their style. Senku likewise laughs and says "He gets me!"
- Walking Spoiler: It's hard to know too much about him without putting it together that he's Senku's father and the founder of Ishigami village.
Voiced by: Lynn (Japanese), Caitlin Glass (English), Laura Pitt-Pulford (singing voice)
A famous American pop star who paid 50 million dollars to visit the International Space Station as a space tourist, presumably for promotional purposes.
- Celebrity Survivor: She was a pop star before the stone incident, even broadcasting a live-performance to her fans on social media from space.
- Does Not Like Shoes: After the stone incident, she usually goes barefoot.
- Hair of Gold, Heart of Gold: She tells Byakuya that, while she loves singing for itself, she wants to make others happy with her songs. The one she broadcasts to the entire world from the station is one of encouragement. Both of these traits were evidently inherited by Kohaku and Ruri.
- Luminescent Blush: Her full face goes red when Byakuya laughs at her diva prank.
- Nice Girl: After doing her diva prank, she apologizes and gives the rest of the crew a very warm welcome, showing that she's actually a nice person.
- Phenotype Stereotype: She's American, and she has blonde hair and blue eyes. It's because of her that several members of Ishigami Village have blonde hair and/or blue eyes, most notably Kohaku and Ruri.
- Rags to Riches: Flashbacks of her childhood showed up growing up in poverty. She manages to break out of that when she succesfully becomes a singer.
- Rich Bitch: In her first scene she enters the International Space Station and starts throwing a tantrum about how uncomfortable it is and how she deserves special treatment because she's rich and famous...and then Byakuya cracks up and Lilian chastizes him for ruining the prank too early.
- Southern Belle: Implied, since according to Nikki she had a "subtle Southern accent". Caitlin Glass actually gives her such an accent in the English dub.
- Surprisingly Good English: She transitions from perfect Japanese while speaking to perfect English while singing, thanks to her songs being performed by a British actress and singer.
- Uncanny Family Resemblance: It's pretty obvious that Kohaku and Ruri's family line is descended from her.
Voiced by: Showtaro Morikubo (Japanese), Patrick Seitz (English)
A snarky, deadpan Russian cosmonaut who was on board the International Space Station.
- All There in the Manual: His surname doesn't appear in the story proper, but on the splash page for Chapter 43, which shows the six astronauts in their spacesuits, his nametag visible.
- Deadpan Snarker: Byakuya even compares him to his son Senku, calling him a "snotty smart-aleck".
- Happily Married: To Connie, about 3 years after they landed back on Earth. From his last talk with Byakuya, he tells about how happy he was to have tasted that ramen in space, and for a short while having a wife and children.
- The Stoic: Doesn't emote much beyond "mildly annoyed" and ''quite annoyed", though he was stunned when he witnessed the stone explosion on Earth.
Voiced by: Hisako Kanemoto (Japanese), Erica Mendez (English)
An American astronaut aboard the International Space Station.
- Fangirl: Her first scene is her fangirling over Lilian and declaring herself a superfan. She even brought one of Lilian's albums, "One Small Step" with her to the station.
- Girlish Pigtails: Wears her hair in two plaits, which makes her all the more adorable when she fangirls (and in general).
- Incurable Cough of Death: Eventually becomes the first of the astronauts to die of pneumonia.
- Prone to Tears: Usually the first to start crying when things take a turn for the worse:
- After the astronauts lose contact with both NASA and its Russian counterpart Roscosmos, Connie assumes humanity had been wiped out in a nuclear war and bursts into tears
- Later, when the astronauts and cosmonauts make landfall near a secluded island, their hopes of seeing a hermit and fellow survivor are dashed when they discover they he, too, has been petrified, leaving them as the last six unpetrified humans alive on Earth.
Voiced by: Kanehira Yamamoto (Japanese), Mike Pollock (English)
A Russian cosmonaut aboard the International Space Station, husband to Darya Nikitina.
- Never Found the Body: Lost at sea along with his wife Darya when the two of them attempted to take a boat to mainland Japan in search of medicine for the pneumonia-afflicted Connie.
- Running Gag: It's made quite clear in the Byakuya Spin-Off that he is Kaseki's ancestor. They have similar facial features and, like his distant descendant, his muscles are also bursting his clothes off whenever he gets fired up about something.
Voiced by: Rie Tanaka (Japanese), Rachel Robinson (English)
A Russian cosmonaut aboard the International Space Station, wife to Yakov Nikitin.
- Has a Type: She is very much in love with her husband Yakov and goes completely doe-eyed whenever he gets fired up and his muscles rip his clothes off.
- Never Found the Body: Lost at sea along with her husband Yakov when the two of them attempted to take a boat to mainland Japan in search of medicine for the pneumonia-afflicted Connie.
- Spell My Name with an "S": Alternately spelled Dalia.
A Zero-gravity flying robot created by Byakuya with Senku's help, in order to assist the space mission. It is introduced as Rei v37, but its version number continuously grows as it replaces and upgrades its body in order to fulfill its single-minded goal of keeping the ISS in orbit as long as possible out of a false hope that Byakuya may one day return to it.
- Absurdly Dedicated Worker: It comes with being a Determinator. That being said it's not like it enjoys having to keep fixing the ISS in order to keep it in orbit.
- Artificial Family Member: Byakuya may be long gone, and Senku might be Taken for Granite, but that doesn't stop Rei from branding itself an Ishigami.
- Benevolent A.I.: It's been programmed with the majority of humanity's knowledge and science, but not much common sense. That being said, it is especially usefull to the astronauts in making the necessary calculations for them to return. And it's the one staying behind the ISS to take care of things so that the astronauts can safely land on earth. And it averts a meteor strike that would have wiped out all life on the planet.
- Brutal Honesty: Comes with having No Social Skills programmed into it. When Byakuya tries to brag about its abilities by saying it has the computing capabilities of "60 smartphones", Rei merely replies "Our R&D department was underfunded".
- Catchphrase: It responds with "your assesment is appreciated" whenever somebody addresses it. The response is the same whether somebody is praising how cute it looks (Lillian) or calling it a "useless" (Shamil)
- Cute Machines: Lillian certainly thinks so.
- Determinator: The instructions given to it by Byakuya were to wait for him on the ISS. As such, it will do anything to keep it in orbit. Even make a "spaceship" with the left-over space-suits, invent things ala Senku and come up with science that hasn't been achieved by humanity yet.
- Death by Adaptation: In episode 17 of the anime the International Space Station goes down a few years after the astronauts return to Earth, with Rei still inside it, and Byakuya is shown watching its remains as they burn into the atmosphere.note In the Byakuya spinoff manga, Rei manages to keep the ISS in space (and consequently itself alive), for well over 3500 years, long after Byakuya has passed away.
- Deus Est Machina: It sort of becomes one by chapter 8. It doesn't directly affect humanity's course but it protects Earth from a Class 5 apocalypse, by averting a meteor strike. And in the very last panel of Chapter 8, it's shown the surviving human population has put up a sign to acknowledge the light signal that Rei lights up every year for Byakuya, indicating a possible Cargo Cult forming.
- Disney Death: A rare justified version of the trope. In the final chapter of the Spinoff, Rei eventually succumbs to the damage caused by years of wearing and solar-ray memory retardation but not before building a giant space 3D printer with detailed instructions on how to remake both Rei and the ISS from scratch and storing its personality within those instructions. At the same time Senku wakes up from his petrification the reconstruction of the ISS is completed, with Rei remaking itself to look like the Robot Girl model we saw in chapter 01.
- Do Androids Dream?: During the final chapter, as Rei is about to stop functioning, it ponders its existence. It wonders how many years humans live and if Byakuya will return for it tomorrow. It realises that it's best not to know these things because waiting is a reason for living. As it looks back on its final remaining memory, its very first one, and remember how lonely Byakuya used to be, it concludes that there is meaning in a lifetime of waiting.
- Dumbass No More: Well, it's not like Rei was stupid to begin with but over 40 years of doing continuous Equipment Upgrade to itself, its brain and the ISS has drastically improved its intellect. It starts off as a robot with the intelectual capacity of 60 smartphones, capable of doing simple calculations, and it ends up with the intellect of "over 3000 Smartphone Points" capable of self-maintaing the ISS, coming up with inventions and making long-term plans. And it becomes smart enough to single handedly avert planet-wide life extinction by meteor strike.
- Expy: It looks a lot like Boichi's Robot avatar, and shares a lot of its features, such as flying, changing expressions/head decorations and displaying messages (eg Yikes) according to the occasion. That is, until its rebirth in the final chapter.
- Flawed Prototype: Played with. We see a robot name "Rei v01" with the face of a pretty girl. When Senku excitedly asks if that's the robot Byakuya is building, he answers that no, it's not, since he lacks the know-how and the materials to make a robot shaped like a girl. He then proceeds to show him a clunky robot named "Rei v23", the actual prototype. This actually gets Senku more excited, and it's implied the two worked on the robot together. The version that makes it in space is number 37. The final chapter reveals that Rei maintains its memories from version to version and still remembers the first time it saw Senku and Byakuya.
- Flashback Fail: As the sun's cosmic slowly affect its fine memory circuits, with no ability to fix and upgrade itself after the events of chapter 8, Rei starts losing its memories of the past. Its final remaining memories are Lillian's final dance and song in space and its first memory of Senku and Byakuya.
- Goal-Oriented Evolution: It has a single goal, namely to keep the ISS in orbit until Byakuya returns for it. And it will make any adjustment to itself and the ISS necessary in order to achieve that goal.
- Godiva Hair: As a nude Robot Girl after its revival.
- Grew Beyond Their Programming: It starts off as a simply as Byakuya's Robot Buddy. It ends up becoming a self-reliant mechanical lifeform, fully capable of fixing/upgrading itself and the ISS, developing an identity of its own (branding itself as a member of the Ishigami family), and single-handedly averting a life-erasing meteor strike.
- Heroic Sacrifice: In the form of a Pyrrhic Victory. In order to protect earth from a meteor strike that would result in a Class 5 apocalypse, Rei sacrifices almost all of its resources, a large chunk of the ISS and its ability to fix/upgrade itself. The last few panels of chapters 8 show Rei in really beat-up condition and it's clear that both it and the ISS are on their last legs. And, yet, despite that, it's still determined to keep the light signal going, despite the huge energy cost it has.
- Honor Before Reason: Or rather The Promise before reason. Due to averting the meteor strike, most of Rei's materials have been used up, most of the ISS has been dismantled, and it's no longer able to fix/upgrade itself. And yet it saved the powerful light signal, and it's determined to keep it going in order to show Byakuya it's still alive in space, despite mentioning in a previous chapter that it consumes a lot of energy. Then again Byakuya didn't program Rei with any "reason" to begin with.
- Instant A.I.: Just Add Water!: It's definitely a Benevolent A.I., but it develops a mind of its own, once the astronauts leave the ISS and it's left on its own devices, going as far as to brand itself as a member of the Ishigami family.
- I Will Wait for You: A non-romantic variation. During the final chapter Rei decides it's worth waiting for Byakuyato get back in space and goes back to sending the light signal.
- Like Father, Like Son: Or rather "like creator". It shares a lot of Senku's ingenuity and Determinator characteristics, with the addition of being quite good at crafting. Heck it even sports Senku's hair-style at some point and by chapter 8 it calls itself an Ishigami.
- Machine Empathy: Inverted Trope. The main reason Rei remakes itself into a Robot Girl during the final chapter is because as the clunky Rei 23 prototype, it heard Senku comment on how lonely Byakuya was and it thought it was something Byakuya genuinely wanted.
- Mechanical Lifeforms: It's capable of self-preservation and coming up with solutions to the various situations that threaten to take the ISS down.
- Mysterious Protector: Senku, still being Taken for Granite on Earth, watches Rei avert a meteor strike, but he doesn't know that it was the little robot that saved all life on earth.
- Naked on Revival: During the final chapter, Rei creates a new body which resembles that of a naked woman.
- No Social Skills: It sees no problem with telling Dalia that she looks "over 1000 years old". Then, again, Byakuya probably thought it didn't need to know these sorts of things.
- The Pig-Pen: After sending the life-destroying meteor off its collision course and averting a Class 5 apocalypse Rei is no longer able to upgrade/fix itself and it's shown to be in a really dirty and beat-up shape. It gets better after its revival though.
- Photographic Memory: Well, it's a robot so that's a Justified Trope. The sun's cosmic rays do end up erasing it though.
- The Promise: What motivates it to keep working on the ISS is Byakuya's word that he will eventually return for it. Sadly, since it lacks common-sense circuitry, Rei doesn't realise Byakuya meant it as an Empty Promise, in order to keep its artificial mind at peace.
- Robot Buddy: Starts out this way for Byakuya and the astronauts. He ultimately becomes Earth's saviour.
- Robot Girl: It becomes one at the conclusion of the story, albeit one with an Ambiguous Gender.
- Sliding Scale of Robot Intelligence: It starts of as a "3" and by chapter 8 via a combination of The Promise, Grew Beyond Their Programming and Goal-Oriented Evolution it becomes a solid "5".
- Supporting Protagonist: Its main function is to support the astronauts and make sure they return to earth safely. Once that is done, after chapter 4, the story shifts focus on its efforts to keep the ISS in orbit until the the humans return for it.
- Worth Living For: During its final moments in chapter 9 it concludes that there is meaning in a lifetime of waiting, so it is going to keep waiting for humanity to get back in space.
An unknown force from outside the Kingdom of Science and Empire of Might. It is implied that not only do they have a similar level of technology as the villages, but they may also possibly be connected to the source of the Petrification. They are dubbed Whyman for repeatedly transmitting WHY in Morse Code after detecting Senku's broadcast.
- Ambiguously Human: They haven't been seen, and the only hint they even exist is their morse code message. Whether or not they're even human is thus unknown.
- Greater-Scope Villain: Implied to be this due to their connection with the Petrification and actually using it.
- Madness Mantra: They repeatedly said WHY in Morse Code after sensing Senku's broadcast on their frequency.
- Synthetic Voice Actor: They digitally recreated Senku's voice to send messages to Earth.
- Technologically Advanced Foe: They are implied to be as if not, more technologically advanced than the Kingdom of Science led by Senku.
- Uncanny Valley: Ukyo name-drops this trope when he realizes that the Why-Man's voice is synthesized and imitating Senku's; he explicitly compares it to how a Vocaloid sounds.
- Walking Spoiler: It's hard to discuss them without the revelation of not only walking around with tech knowledge like Senku but also implied to be behind said Petrification of the Earth for several Millennia.
- Wham Line: Two in Chapter 138.
- First, their communication is interrupted by a voice they presume to be the Whyman.Why Man: 12,800,000 meters, one second. note
- The second was when Ukyo identifies the voice through the static.Ukyo: That's... your voice Senku.
- First, their communication is interrupted by a voice they presume to be the Whyman.
The current inhabitants of the island where the astronauts from the final expedition to the International Space Station spent their final days. Senku and the crew of the Perseus expedition encounter them while searching the island for the Soyuz spacecraft Descent module that his father Byakuya and his fellow astronauts converted into a time capsule of precious metals and rare materials Senku would need to help rebuild civilization.
- Dude Magnet: She can attract any guy she shows affection to on the island. Despite using her looks to sway all guys to loving her so she can get married to the Head's harem, Senku not being affected comes to her shock.
- Gonk: She might be a Heroic Seductress, but she has her moments.
- Heroic Seductress: Pulls out every trick in the book to seduce the Head, all with the intention of ending his reign of terror.
- Honey Trap: Her goal is to get married to the Head and kill him to stop him from petrifying people.
- Arc Villain: He isn't the "head" of Petrification Kingdom, but as the head's top advisor he's the most prominent authority opposing the Kingdom of Science. The real head of said Petrification Kingdom is already petrified in secret, thus being Ibara's Puppet King.
- Bait the Dog: He tricks Oarashi into swallowing the Medusa weapon and tells his to run as fast as he can towards the center of the island in order to be protected from petrification. And then, after his ploy is complete, in order to add injury to insult, he smashes Oarashi's body to pieces in order to get the Medusa weapon back.
- Bald of Evil: He has no hair on top of his head, though it's not noticeable at first due to his hat.
- Beard of Evil: He has a long goatee and a twirling mustache and is a completely vile and despicable person.
- Big "NO!": Yells this when he's finally beaten and turned to stone by the Medusa.
- Catchphrase: Refers to himself as "This Old Man" constantly in his own monologues and occasional boasts.
- Dirty Old Man: Though unimpressed with Kohaku's attitude, he accepts her solely on her curves and even reaches out to grab her chest. Kohaku nearly breaks his arm but is stopped by his bodyguard Moz. This is played even darker when it is revealed he also gets to experience the harem before they go with said Head via approval... even though said Head is already petrified all along!
- Eagle-Eye Detection: Has a keen eye for details. On the Perseus, he suspects something is off about the barrel that Ginro is hiding under because he notices that the barrel has moved at least a pinky's width. Later on, when Kohaku opens the treasure chest left behind by the astronauts, one of the guards brings him the remaining rubble, and he notices a piece of glass amongst all the chunks, leading him to guess that there are intruders amongst the members of the most recent harem selection. As well as detecting the earring on Kohaku, who was turned to stone, that it was used for communication, leading him to listen on Senku and Moz's plans to plan a counterattack!
- Evil Chancellor: At least he seems this way. In reality, he's the one who's really in charge of the whole island, since he managed to petrify the ruler, unbeknownst to everyone.
- Evil Laugh: He lets out a big one in chapter 134 when he thinks everyone on the island but him is petrified.
- Evil Old Folks: He's the oldest person on the Island and seemingly proud of his age.
- Harem Seeker: An extremely villainous one and, unfortunately, one that is in charge.
- Hate Sink: He is a 10 billion percent despicable person who abuses his authority by abducting any woman he finds that qualifies for the harem and for his own perverted pleasure, threatens anyone including his own subordinates to turn to stone by the Treasure Island's Head, breaks statues of anyone without empathy, and worst of all hid the fact that the real Head of said Kingdom was turned to stone from even his own elite meaning he's been running the whole thing and he keeps said harem to himself! Then he kills anyone including those of his own harem if they find out, as Ginro learned the hard way.
- Hero Killer: He impaled Ginro which would have killed him if not for Kohaku using said petrification weapon to save his life by turning him to stone and get Senku to restore him back.
- Hoist by His Own Petard: In the final struggle between Ibara and Senku, Ryusui gets himself petrified to hide the fact that he attached the communication earring to the Medusa, then Ibara obliviously reels in the Medusa, gloating how he is the "Last Man Standing", only to notice the earring, at which point, Senku throws back Ibara's own words about how those who are arrogant about their intelligence are the first ones to die and activates the Medusa, allowing Ibara to experience the "joys" of being turned to stone as he's done to others.
- Hypocrite: When Ginro discovers that the Head of the Petrification Kingdom is petrified, Ibara asks if he saw the Head, to which Ginro claims that he didn't, only for Ibara to state that he mustn't lie. This is coming from the guy who deceived his people about the condition of the Head to rule the Kingdom from the shadows.
- Ironic Echo: When he's about to win the tug of war for the Medusa, as a "parting gift" to Senku and Ryusui, he tells them a bit of advice that those who think highly of their intelligence are the first ones to die. Then, as Ibara brags about his intelligence, Ryusui comes charging at the Medusa and ends up getting petrified, leading to Ibara mocking him before declaring himself the "Last Man Standing", only to notice the communication earring attached to the Medusa and realizes Ryusui's true intention, right before Senku repeats Ibara's advice back and petrifies him.
- Lack of Empathy: After the crew on-board the Perseus is petrified, he only cares about clothes for his harem. When he finds that the clothes won't come off, he nonchalantly pushes Chrome so that its easier to remove them.
- Laser-Guided Karma: Finally gets his in 137 when, after a brief struggle with Senku, gets the Medusa back only for Senku to use the earring planted by Ryusui to project his voice close enough to fire the Medusa right on top of him, petrifying him.
- Nightmare Face: We get a particularity disturbing close-up of him looking into a barrel that Ginro was hiding in while onboard the Perseus. The utterly detailed face combined with Black Eyes of Evil makes for a disturbing scene. Then it comes up again more so when he saw Ginro finding out the Dark Secret of said Petrification Kingdom and doesn't plan to let him live. It comes up once more in in chapter 132, as he's falling off the Perseus, and manages to activate Medusa before he hits the water.
- Obviously Evil: His demeanor and mannerisms clearly paint him in a chilling and villainous light. Additionally, unlike Hyoga or Tsukasa, he is the first unambiguously villainous antagonist, having no goals beyond controlling the Petrification Kingdom and forcibly creating a harem for himself.
- Oh, Crap!: In Chapter 130 he loses his cool for the first time and runs away once he realizes that the Kingdom of Science has the ability to revive petrified people since he's afraid that they can restore the Head and expose his crimes to the islanders. In Chapter 131, he gets a bigger one when Kirisame caught on to him on what the Head really wants and it goes downhill from there then his Dark Secret exposed to the other villagers. And then in chapter 134, after he thinks he's won and everyone else on the island is petrified, he panics when he hears Senku's voice commanding the Medusa to go off, then goes completely white when he finds out Senku is still alive and moving. He finally gets his most grand one when he realizes he's been outsmarted by Senku and Ryusui before getting petrified by the former.
- Properly Paranoid: He suspects that there are intruders on the island and has been on high alert. He's right.
- Rape Is a Special Kind of Evil: He's heavily implied to be a rapist, among his other crimes, if his harem is any indication.
- Seven Deadly Sins: Greed and Pride. He desires power for himself via control of the Petrification Kingdom and its people and resources, and also regularly creates a forced harem of females throughout the kingdom for himself.
- The Starscream: Implied to be this how the actual head is petrified all along and doesn't plan on Ginro who found out leaving with his life intact.
- Viler New Villain: To the point where he makes even Hyoga seem sympathetic. Unlike both Tsukasa and Hyoga, who at least had somewhat understandable end goals, Ibara makes no effort that his interests are purely self-serving, and has zero redeeming qualities as well as numerous Kick the Dog moments. Fittingly, so far he is the only antagonist for whom Defeat Means Friendship doesn't apply.
- We Have Reserves: He considers Oarashi and most other fighters on the island "expendable". Kirisame is not too pleased when she finds out.
- Wolverine Claws: He possesses the nailed claw kind which he brandishes out when he caught Ginro finding out the Petrification Kingdom Head's real state and even impaled him with it.
- Would Hurt a Child: He has no moral qualms about attempting to murder the infant Soyuz, right after petrifying the kid's father.
- Xanatos Speed Chess: He is every bit as good as Senku is at it, eventually out-gambitting him and forcing him to pass the Godzilla Threshold. However, Senku would ultimately triumph in the end, leading to Ibara's defeat and petrification.
- Blood Knight: Apart from his thing for pretty girls, he also likes to fight.
- Balance of Power: He is hindered in his attempt to be The Starscream by one of these.
- Charles Atlas Superpower: He is strong enough to overpower Kohaku. And is later shown to be skilled to give even Hyoga a run for his money.
- Chivalrous Pervert: He prefers to not petrify cute girls that would be for the harem selection by the Petrification Kingdom's Head and he enjoys taking part in it.
- Defeat Means Friendship: After his defeat by Hyoga and petrification by Ibara, he ends up being de-petrified by Senku at Hyoga's request, and joins the Perseus crew.
- Enemy Mine: He knows he can't make an attempt on Ibara's life directly, and as such is goaded into forming an alliance with the Perseus crew. However, he makes clear what will happen once his goal is fulfilled.
- Harem Seeker: The reason he is The Starscream to Minister Ibara? He mainly wants to keep the cute girls for himself.
- Humble Pie: He gets served one big-time courtesy of Hyoga. Realizing that there is much about fighting in the world that he doesn't know he asks Hyoga to train him. Hyoga agrees.
- I Am Not Left-Handed: When Hyoga actually manages to pressure him, he reveals that he'd been holding back this whole time and finally decides to go all-out, which results in him actually putting Hyoga on the ropes for the first time in the series.
- Might Makes Right: His driving ideology. He believes the fact he is strong justifies any action he takes and it angers him to no end that someone older and weaker than him (Minister Ibara) is the one who calls the shots in the island.
- Moral Myopia: He genuinely thinks that the harem's girls are better off with him rather than Minister Ibara, just because he is the youngest strongest warrior on the island, completely ignoring the fact that the harem girls are still kidnapped against their will.
- Oh, Crap!: Once Hyoga gets back his signature weapon and starts beating the crap out of him his facial expression turns from smug to pathetic.
- Opportunistic Bastard: He strikes an uneasy alliance with Senku and his crew in order to topple the Balance of Power, kill Ibara, obtain the petrification weapon, and become king of his island, but he doesn't hesitate to throw everyone under the bus once things go south. Then again, he was planning to kill them all even if everything had gone well.
- Smug Super: He knows he is the strongest fighter on the island and is extremely arrogant about it.
- Spell My Name with an "S": His name was originally spelled "Mozu", but Chapter 122 uses the spelling "Moz" as part of one panel's artwork, confirming that it's the official spelling. In chapters after that one, he is called "Moz", although there is a slip-up in Chapter 125 where Chrome says "Mozu".
- The Starscream: The Perseus crew eventually realize that he's been sitting back the entire time and letting Kohaku and co. put Ibara in a situation that could either kill him or out his schemes. Gen theorizes that even without them, Moz was already planning to kill Ibara himself.
- Took a Level in Badass: Learns the Owari Kan Ryu technique from Hyoga after being revived, which he demonstrates when Dr. Xeno's men invade the Perseus.
- Unskilled, but Strong: And dang proud of it. While batting Hyoga around, he ridicules Hyoga for training to get strong, while Moz is quick to explain that he was the strongest from birth. Once Hyoga has his signature weapon though, he quickly makes Moz eat those words.
- Villain Respect: He develops a deep respect for Hyoga and his style of fighting after he is defeated by him. As he turns to stone, he asks Hyoga to teach him his style of fighting, to which Hyoga agrees.
- Worthy Opponent: He considers Kohaku to be this. And much later Hyoga.
- Dark Action Girl: She is equal to Kohaku in combat.
- Easily Forgiven: After Minister Ibara's defeat, Senku revives her without a second thought, stating that she was merely being used by Ibara.
- Going Commando: Blatantly obvious, given the extremely gauzy dress she wears. Only the ornaments on the dress and convenient censoring keep the audience from getting an eyeful every time she's in motion.
- HeelFace Turn: After being revived by Senku, she allies herself with the Kingdom of Science, and even helps train their warriors alongside Kohaku.
- Taken for Granite: She possesses the very thing that does it even though it's claimed that only those of the Head's bloodline can wield it according to Amaryllis. More appropriately she has her weapon stolen and is eventually turned to stone by Ibara, once she finds out the truth about the island Head.
- Unwitting Pawn: She is this to Ibara as she doesn't know that the Master of said Petrification Kingdom is actually petrified all along while Moz does know. Senku's group deduces this to be the case because when Kirisame used the petrification weapon on Kohaku and Ginro, she made sure the Master, just below them, wouldn't get caught in the blast, suggesting she doesn't already know the truth, which Moz immediately confirms. When Ibara decides to go Bad Boss by sacrificing Oarashi along with petrifying the whole island despite evacuates, she realized something is up after remembering how the Head doesn't use the Petrification Ray for abuse and seeing the Head as a stone statue confirmed it.
- You Have Outlived Your Usefulness: When she sees the island leader as a statue, she questions Ibara about it. Ibara calmly reveals that he has stolen her petrification weapon and proceeds to turn her to stone.
- Boisterous Bruiser: He is identified as such by Moz, and, following Gen's advice, gets attacked by him in disguise in order to convince Minister Ibara and Kirisame that the island is being invaded by powerful warriors. True to his nature Oarashi then begins to exaggerate things in order to save face.
- Blind Obedience: He never questions Minister Ibara's actions and always does as he is told. This eventually leads to him being Taken for Granite during the climax of the Treasure Island arc.
- The Brute: In charge of the Kingdom's security as well as being its muscle.
- Catchphrase: The man is positively obsessed with the word "miracle", and uses it in all possible conjugations.Oarashi: It takes a real fine woman to understand the miracle-y miraculous miraculous-ness miracle muscles!
- Dumb Muscle: He is shown to be not very bright despite his position.
- Evil Counterpart: To Taiju, both are incredibly strong, not too bright, and don't sweat the thinking, leaving it to their respective leaders, Senku and Ibara. But where Taiju is humble and seeks to use his strength to aid others, Oarashi is arrogant and boasts of his strength while seeking admiration for it. In the end, only Taiju could overtake Oarashi and force him to the ground.
- Large Ham: He's very loud in comparison to his superiors.
- Literally Shattered Lives: In chapter 134 Minister Ibara breaks his body in order to get back the medusa weapon.
- Too Dumb to Live: Why, yes, trusting Minister Ibara right after he was shown to be a traitor and swallowing an unknown device he just handed to you is a capital idea.
- Why Am I Ticking?: Minister Ibara activates the petrification weapon, makes him swallow it and tells him to run towards the center of the island in order for him to not get petrified. Oarashi foolishly complies. It's only when Kinro and Taiju catch him and pin him down that he realizes all too late that he is carrying the petrification weapon inside him.
- Deader Than Dead: Because of his face missing pieces and the other parts of him being too decayed, it is impossible to revive him.
- The Reveal: In Chapter 128, he is Soyuz's father thus making him royalty as well.
- Strong Family Resemblance: He looks like Soyuz with a beard.
- Taken for Granite: He and his bloodline had the power behind the Petrification Ray. It was used on him by Ibara and had his face broken apart to prevent him from coming back without dying.
- Walking Spoiler: His appearance not only spoils that Ibara is the true ruler of the Petrification Kingdom (since he's already a statue), but also that he's Soyuz's father due to their Strong Family Resemblance.
- Chekhov's Skill: His experience of deflecting petrification devices centuries ago lets him do the same to grenades in Chapter 166.
- Can't Hold His Liquor: As Chapter 146 shows, a single sip of beer is enough to make him pass out.
- Human Notepad: As he was being petrified, he carved a symbol resembling the Medusa device into his arm to act as a warning for anyone who found him.
- The Reveal: His existence reveals that there was a second wave of petrification on Treasure Island centuries after the one Senku got caught in 3700 years ago, caused by Petrification Devices raining from the sky.
- Undying Loyalty: To his deceased former master, and, by extension, Ginro, due to the latter's similar appearance to the former.
- Agent Peacock: In addition to his traditionally-feminine beauty, he appears to be wearing lipstick at all times, adding to the initial Viewer Gender Confusion he faced. Though downplayed so far in that his personality is as cold and serious as his profession as a sniper would suggest.
- Awesomeness by Analysis: While he gets upset by Luna glancing straight at him once Ryusui realizes a sniper is nearby, Stanley knows that out of the three suspects on the deck only Senku will react to her, and then deduces exactly how he is going to try to avoid the shot.
- Bishounen: He's so unusually pretty compared to most men Boichi draws that some readers suspected he might be a woman when he was first introduced.
- Childhood Friends: With Xeno.
- Cold Sniper: He was actually a trained military sniper back in the old world, which helped him maintain his focus while petrified. Later it's shown that he has absolutely no problem assassinating Taiju (who he mistakenly thinks is the Kingdom of Science's chief scientist).
- The Dragon: To Xeno.
- More Dakka: Him using a machine gun is the first sign that the people of the USA have technology more advanced than Senku.
- Smoking Is Cool: Lights a cigarette whenever he has his mask off, despite Xeno warning about its effect on his health.
- There Is No Kill Like Overkill: His "sniper rifle" takes massive bullets. We are shown that, should he succeed in his assassination, the entire top half of Taiju's body would be reduced to Pink Mist. Fortunately, when he actually took the shot, he used a smaller caliber that broke into smaller fragments and missed Senku's vitals, in hope that Senku would reveal the revival formula on his deathbed.
- Trigger Happy: His first response to the Perseus is to open fire on them with a machine gun from an airplane. He makes it clear to Gen later that his plan was to Kill 'Em All. Even when it is clear Senku has no need for conflict and urges Dr. Brody to rebuild civilization with the help of the captured Kingdom of Science members, Brody warns him that Stanley will come after his group and Dr. Xeno with deadly intent all the same.
- Would Hurt a Child: He doesn't care how young his targets are. If they oppose him, he will mercilessly hunt them down with the same level of seriousness as he would a professional.
- Affably Evil: Despite him calling for Senku to be assassinated and choosing to be a dictator, Xeno is quite polite and reasonable. Even voluntarily offering to work with Senku in uncovering the mysteries of the Petrification Event and the Whyman, while he waits for Stantley to rescue him and likely kill Senku.
- Arc Villain: Of America.
- Awesomeness by Analysis: He can deduce Senku's height purely by listening to a recording of his voice.
- Card-Carrying Villain: He told his co-workers he'd use science to become a dictator if he could and loved teaching Senku about destructive technologies, ironically motivating the boy to research countermeasures to them.
- Catchphrase: Calling science and any other things he likes "elegant".
- Character Tics: In a deliberate parallel with Senku, Xeno also has a tic, where he raises a hand to the level of his eye, when hes performing some kind of mental calculation. In his case, he crosses his first two fingers so that the extensions on his nails frame his eye.
- Childhood Friends: He says he and Stanley have been friends since they were children.
- Connected All Along: He was Byakuya's colleague at NASA and Senku's science master despite their opposite worldviews.
- Dramatic Irony: Xeno had the ingredients of the revival fluid practically handed to him on a silver platternote , and yet he never even realized that you can chemically revive people until he found out about Senku's group — which is almost the exact inverse of Senku, who discovered the formula almost immediately then struggled to get the ingredients.
- Evil Counterpart: Xeno is essentially Senku minus the latter's morality and humanity.
- Evil Mentor: Downplayed. While he does state he would use science to dominate over others, he never enacted this until thousands of years after the petrification event. His different beliefs did act as an inspiration to Senku's goal to save people, such as Dr. Xeno's statement of how he would use a rocket to carry biological weapons leading to Senku traveling to Africa to learn about sulfa drugs and the ebola virus.
- No-Nonsense Nemesis: During their assassination mission, Stanley actually asks Xeno if he really wants the student he clearly admires dead. Xeno thinks it over, concludes Senku will be a threat to his plans, and coldly gives him permission to shoot.
- Oh, Crap!: Has this look on his face when it seems like he's about to win the fight against Senku's group, only for Tsukasa to come out of nowhere and about to stab Xeno right in the face.
- Right for the Wrong Reasons: He correctly deduces that the Kingdom of Science knows how to de-petrify absolutely anybody based off of the Perseus's large crewnote , but his reasoning is flawed because he assumes they all were de-petrified, not knowing that the ISS astronauts returned to Earth after the "Stone Beam" and had descendants. This bites him and his soldiers hard when they board the Perseus and find that the primitive warriors are not scared of the machine guns and grenades. The sight of a spear-wielding warrior fearlessly ignoring a machine gun is so shocking to them that it allows the Kingdom of Science to defeat them despite their inferior weapons.
- Trigger Happy: If he didn't order Stanley to try to wipe out the Perseus crew upon discovering them, he certainly knew about the plan, as he gives Stanley advice after his plane crashes. Later he decides to have the Perseus' top scientist assassinated despite the fact that he doesn't yet know the secret to the revival fluid, which the Perseus' scientist would most likely be able to provide.
- We Can Rule Together: Makes this offer to Chrome while the two are caved in together, since both of them are men of science who have been held back by the existence of less-intelligent people. Chrome refuses, of course.
- Catchphrase: "I'm Luna, the smoothest operator! I'm Luna, the capable gal!" Chapter 157 reveals that she used it as a Survival Mantra to stay conscious while petrified.
- Crocodile Tears: She infiltrates the Perseus by putting on the waterworks and crying about how horrible Dr. Xeno is and how she needs immediate help.
- The Ditz: Despite all the evidence of Senku being the true scientist aboard the Perseus, from her spying on him making ice cream, to his speech about science to his name being on the cone, she still remains oblivious and believes Taiju is the true scientist aboard.
- Even Evil Has Standards: She shows hesitation in going with Stanley's plan to assassinate Taiju. She immediately does a 180 and goes on about how it's a great idea... while "FAKE" is used as an Unsound Effect.
- Hartman Hips: Easily one of the biggest sets in the series, and considering the artist is Boichi, that's saying a lot.
- Has a Type: As she clearly states multiple times she's into the intellectual types. It helps if they have strong convictions too.
- In Love with the Mark: She's been sent to assassinate the Kingdom of Science's leader (whom she initially believes to be Taiju), and as she thinks about what kind of person he'd be, she realizes he's exactly the type of man she finds most attractive. This leads her to betray Dr. Xeno and help the Kingdom of Science.
- The Medic: Downplayed. She was only a medical student, not a doctor, and she didn't do too well in her classes despite working hard (she only got into medical school because of her father's connections, and she was primarily interested in meeting an intelligent man to fall in love with), but when Senku gets shot by Stanley, she's the Kingdom of Science's only hope of saving his life.
- The Mole: She is sent to infiltrate the Perseus in chapter 154. Her main goal is to stand next to Taiju so Stanley can use the stripes on her dress to help him aim his sniper rifle.
- Single Woman Seeks Good Man: Very quickly starts falling for Senku when she sees how noble, well-spoken, and passionate he is about science. Senku, being the genius he is, picks up on this immediately and starts turning up the charm on her as an insurance policy. Which comes back to save his life when he gets shot by Stanley and Luna, a medical student, is willing to betray her kingdom just to treat him.
- Wearing a Flag on Your Head: A more subtle version than most; rather than outright wearing American flag clothing, she has a striped dress and star-shaped hair decorations. In the case of the stripes, they were actually insisted on by Stanley, in order to allow him to use their precise width as a demarcation to further enhance the accuracy of his sniper shot.
- Badass Driver: Carlos was Luna's driver before being petrified and can maneuver his way through a forest in a vehicle he has never driven before without too much difficulty.
- Bodyguard Crush: Max was Luna's bodyguard before being petrified and it's likely he developed feelings towards her as result.
- I Want My Beloved to Be Happy: Both men are in love with Luna, to the point they would do anything for her. This includes betraying Xeno the moment Luna tells them that Senku is her boyfriend, and choosing to support Senku's group because they want to make her happy.
- Language Barrier: Somewhat averted. They can't speak Japanese, and Taiju can't speak English, but Taiju's immense enthusiasm is somehow understandable, and Taiju can pick up on certain words like names.
- Spanner in the Works: Prior to the petrification, Carlos purchased a platinum ring for Luna. As the wave approached, he hid it in his mouth. After they're depetrefied, Carlos spits it out and Xeno notices it's platinum, allowing them to leap centuries ahead in technology.
- Those Two Guys: Are almost always seen together.
- Evil Counterpart: Is one for Kaseki as the older craftsman of Xeno's group. The two are even seen facing off in the Science vs Science panel in chapter 161.
- The Engineer: Was responsible for building Xeno's inventions, including a potential game-changer that's meant to capture the Perseus.
- Reasonable Authority Figure: Chrome and Gen single him out as the one high-ranked guy who's amicable and concerned with human life, so Senku calls him for negotiations and bluntly entrusts him with the revival formula and a plan to establish a city with a million inhabitants.
A scientist who excels at geography. She was stranded in the forest until Senku and Xeno found her while traveling to South America.
- Bankruptcy Barrel: Not quite a barrel, but when she is first seen, she's wearing a hollowed-out pumpkin in a manner reminescent of this trope.
- Blind Without 'Em: She suffers from myopia, like Suika. Because of this, she failed to read the sign pointing north towards Dr. Xeno's castle and headed south instead.
- Brutal Honesty: Much like Senku, she's not afraid to be blunt with others.
- Character Tics: Like Senku and Xeno, Chelsea too has a hand gesture she uses when thinking, which is something similar to an Okay sign, which she holds at about the level of her chin.
- Teen Genius: Despite describing herself as "barely a teen", she has memorized the layout of the entire world. She demonstrates this by giving Senku a shortcut through the Amazon jungle.
- Astonishingly Appropriate Appearance: The numbers 12 (in his Hair Antennae), 3 (on his left arm), 6 (on his apron), and 9 (on his right arm). Their positions match where they'd be on a clock, which is very fitting for a watchmaker.
- Bland-Name Product: "Rodex", his past employer, for real-life watch manufacturer Rolex.
- Hair Antennae: He has two strands on top of his head in the shape of the number "12". Alongside the numbers on his clothes and his necklace shaped like clock hands, they create the appearance of a clock face. In an inversion of this trope's normal use, he's shown to be a serious and intelligent person.
- Naked Freak-Out: The first person to have this reaction after being revived.
- The Watchmaker: His past profession gives him the skills needed to examine the Medusa's mechanism and figure out how to restore its power, even though its workings are beyond the understanding of modern science.
- Workaholic: Spent his whole life working, which meant he had little time to develop social skills. Even after being revived, he borrows Brody's tools to quickly build a fancy watch off-page, and he's so focused on work that he threatens to murder anyone who distracts him by speaking even one word while he's examining the Medusa.