Chapter Summaries

Chen Yu and his companions performed the Stone Age’s first surgery, overcoming Reiko’s mistakes and using a risky anesthetic to treat a man’s internal injuries. The patient survived and began recovering while Chen Yu rested, and the settlement turned to winter work and snow sculptures.

• Reiko forgot to inject the patient with anesthetic, so Chen Yu stopped the operation after making an incision and prepared again.
• Chen Yu and the others completed the surgery using an anesthetic mixture, and Miwa reported that the man had been asleep for about three hours and forty-five minutes.
• Chen Yu told Senku the surgery had more or less succeeded, then went to sleep and left follow-up care to Miwa and Xiao Xi.
• Miwa and Xiao Xi wheeled the awake patient out, and Tsukasa forced onlookers to back away before the man was taken to a house to recover.
• Taiju and Yuzuriha began making tools and machines, while Chen Yu used Tsukasa as a model for snow sculptures and Chrome built a sled for winter travel.

Chen Yu sculpted Tsukasa in a discus-throwing pose, prompting a discussion about the Olympic Games and the possibility of holding competitions in the future. The others speculated about Tsukasa and Chen Yu’s closeness, while Ginro’s medal-winning daydream drew Tsukasa’s murderous attention.

• Tsukasa posed for Chen Yu, who carved a snow sculpture of him dressed as a discus thrower.
• Chen Yu explained the Olympic Games to Ginro and the onlookers, and Gen compared them to their grand tournament.
• Chen Yu suggested that a larger competition between their groups might be possible in the future.
• Suika nearly voiced a theory about Tsukasa and Chen Yu’s relationship, but Kohaku covered her mouth.
• Ginro fantasized about winning medals and charming the village girls, so Tsukasa turned a murderous gaze on him.

Chen Yu encouraged Tsukasa as Senku’s treatment stabilized the injured man, while a woman revived in America searched for a token declaring war. Back in Ishigami Village, Chen Yu taught Ruri and the others about medicinal plants and asked Ruri to help him remember the past.

• Tsukasa read Reiko’s report that the injured man was stable, and Chen Yu told him not to seek out Reiko.
• Chen Yu reminded Tsukasa that things could improve, and Tsukasa trusted his promise that a miracle might be possible.
• In America, a revived woman dislocated a man’s arm, stabbed his thigh, and took clothing Xeno offered her.
• The woman dressed and searched for the war token someone had given her.
• Chen Yu taught Ishigami Village residents to identify herbs, and Ruri recalled that some were already recorded in the Hundred Tales.
• Chen Yu asked Ruri to help refresh his memory because he had forgotten parts of the past.

Lilith recalled her long rivalry and growing affection for Chen Yu, whose medical breakthroughs she had tried to shield him from danger. Thousands of years later, she found a surviving gift from him and resolved to beat him someday.

• At an international medical presentation, Chen Yu unveiled an inexpensive treatment, and Lilith angrily confronted him over the danger his announcement could bring.
• Chen Yu insisted he would continue trying to reform medicine, while Lilith tried to protect him by challenging his discoveries and pointing out possible side effects.
• After Lilith fell ill, Chen Yu sent her a longevity lock pendant and a message reassuring her; they continued their verbal battles as he pursued medical research.
• When Chen Yu became harder to meet, Lilith missed him, took up martial arts after hearing he liked them, and began carrying his pendant close as her feelings changed.
• In a world thousands of years in the future, Lilith found the surviving pendant, and Xeno remembered her rivalry with Chen Yu.
• Chen Yu said Lilith had missed her chance to beat him and could no longer defeat him.

Chen Yu struggled to calculate when Lunar New Year would fall, and Senku told him it was still a month away. After Gen discussed a birthday present for Chen Yu, Chen Yu decided to prepare a gift for Senku as well, and he and Gen secretly finished making it.

• Chen Yu spent days covering papers with calculations as he tried to work out when Lunar New Year would arrive.
• Senku recognized what Chen Yu was calculating and reassured him that Lunar New Year was still a month away.
• Senku explained Lunar New Year to Chrome, who had not understood the holiday.
• Gen told Chen Yu he wanted to give him a birthday present, prompting Chen Yu to remember he had not prepared Senku's gift.
• Chen Yu and Gen secretly made a precise birthday present for Senku and finished it within a few days.

Chen Yu and Gen arranged a surprise gathering for Senku, unveiling Chen Yu’s astronomical telescope and fireworks. Gen revealed that the celebration was also meant to welcome the New Year and give Chen Yu a gift, leaving Chen Yu and Senku sharing the villagers’ good wishes.

• Senku, Chrome, and Magma set off to explore the mine while Gen stayed behind to help Chen Yu organize a surprise.
• Five days later, Chen Yu prepared the astronomical telescope at the observatory and waited with the villagers for Senku’s return.
• The villagers blindfolded Senku and revealed Chen Yu’s telescope, which Senku examined as he recalled his childhood.
• Gen launched fireworks and explained that he had arranged the gifts for Chen Yu and Senku together.
• Gen and the villagers wished Chen Yu a Happy New Year, and Senku learned that the celebration included a birthday gift for him.

Chen Yu spent two months secretly building a powerful weapon and emerged with a heavy black stick that Senku recognized as a flintlock. Senku took charge of the firearm while the group wondered whether Chen Yu had also made ammunition.

• After the fireworks, Chen Yu surveyed the launch site and decided to develop a weapon using blueprints he drew the next day.
• Chen Yu gave the blueprints to Senku and old Kaseki, and Senku agreed to make the parts despite not understanding some of them.
• Over the next two months, Chen Yu repeatedly revised his design in a secret base until he completed the weapon.
• Chen Yu tossed the heavy black weapon to Senku and went to sleep, leaving Senku sprawled on the ground from its weight.
• Gen brought Senku another black object, and Senku recognized it as a flintlock, warned everyone not to touch it, and kept it for safekeeping.

After recovering from his exhaustion, Chen Yu went to Chrome’s hut, where Senku and the others were testing armor and paper shields. He sparred with Kinro and pointed out missed counterattack chances, leaving Kinro dejected.

• Chen Yu woke at noon, checked his weapon and the well-maintained Sword Box, then headed to Chrome’s hut.
• Senku explained that the group was comparing the protection of paper shields and Chen Yu’s armor, and Kohaku, Magma, and Kinro described their tests.
• Chen Yu asked for a sparring partner, and Kinro stepped forward to test how much he had improved.
• Chen Yu defeated Kinro with quick staff strikes and explained two opportunities Kinro had missed to counterattack.

Chen Yu explained why mastering one technique through repetition could make Kinro’s Tube Spear Style formidable, then praised a kung fu legend as stronger than Tsukasa. The group reflected on the legend’s early death, while Kohaku briefly imagined becoming strong enough to defeat Chen Yu.

• Kinro showed Chen Yu the Tube Spear Style he had learned and asked for feedback on his improvement.
• Chen Yu called the technique introductory and explained that repeatedly practicing one move could make it powerful.
• Chen Yu quoted a kung fu master, prompting Gen to recognize the words as belonging to an international martial arts superstar.
• Chen Yu described the superstar’s accomplishments and declared that he would have beaten Tsukasa hands down.
• Kohaku mourned the master’s early death and wondered whether she could someday become strong enough to beat Chen Yu.

Chen Yu demonstrated several spear styles to the villagers, and Kinro chose to learn the Qi Family Spear. Chen Yu challenged him to survive against him or defeat him before he would teach it.

• Chen Yu demonstrated the seven routines of the Yang Family Spear and told Kinro that spear techniques should be used to protect people.
• Kinro asked to learn, and Chen Yu said he would need to become his disciple and choose a suitable style.
• Chen Yu demonstrated portions of the Zhao Family Spear, Yue Family Spear, and Qi Family Spear, whose display frightened Kohaku and Magma.
• Senku explained that Ginro had fainted and Suika had taken him to rest with help from someone else.
• Kinro chose the Qi Family Spear, and Chen Yu demanded that he survive against him or defeat him to earn the chance to learn it.

Kinro chose the Qi Family Spear and began training under Chen Yu, while Chen Yu and Senku built a hand-cranked Warning Horn. Hongye Yan watched from afar, still anxious after mistaking the earlier fireworks for firearms.

• Kinro lost every spear match against Chen Yu, who agreed to teach him basic techniques if he could eventually win.
• Senku and Gen warned the others not to interfere with Chen Yu’s decision or probe too deeply into the history behind the Qi Family Spear.
• Chen Yu asked Senku to help make a hand-cranked Warning Horn, and they completed it after three days of assembly and adjustments.
• Chen Yu tested the horn, but Hongye Yan watched from a distance and could not identify the brief, loud sound.
• Hongye Yan recalled how she had mistaken the fireworks for firearms and alarmed Tsukasa’s Empire before Ukyo and Tsukasa clarified what they were.
• Hongye Yan remained frustrated and anxious as she watched Chen Yu and the others gather.

Chen Yu found two bottles of Revival Fluid and prepared to revive Tsukasa’s younger sister, Mirai, before the coming battle. He left Senku to guard the village and set off with Suika to find her.

• Tsukasa sent Ukyo and Hongye Yan on a reconnaissance mission to investigate Chen Yu’s new weapon.
• Chen Yu told Senku that Tsukasa’s empire might eventually turn against him if he failed to meet the people’s needs, and planned to use Mirai to gain Tsukasa’s cooperation.
• Chen Yu searched the place where Tsukasa and the others had worked and dug up two bottles of Revival Fluid hidden beneath a board.
• Chen Yu asked Senku to guard the village and prepare for an enemy attack while he went to revive Mirai.
• Chen Yu recruited Suika to accompany him and gathered clothes for Mirai’s revival.

Chen Yu and Suika searched for the hospital site for days, enduring a wolf attack before Chen Yu found Mirai's statue. Chen Yu revived Mirai, but as he watched her emerge from the tent, he worried that people would no longer need him once they had a Petrification Weapon.

• Chen Yu and Suika used his memories and map to locate a clearing where the hospital might have stood, then began digging.
• After several days of searching, Chen Yu fought off a pack of wolves while Suika stayed in their tent, where a wolf broke in and was killed by Chen Yu's spear.
• Chen Yu butchered the wolves, reinforced the tent, and kept watch while Suika slept.
• Chen Yu found Mirai's statue, dressed her in one garment, and poured Revival Fluid over her.
• Mirai revived and stepped outside with Suika, while Chen Yu felt glad for Tsukasa but worried that the Petrification Weapon would make him unnecessary.

Chen Yu returned to Ishigami Village with Mirai and Suika, then tested the villagers by attacking them in the dark and nearly striking Senku. After revealing his voice imitation and explaining the ambush, he prepared to review the villagers’ mistakes.

• Chen Yu brought Mirai and Suika back to Ishigami Village around one in the morning, carrying wolf pelts and other spoils.
• Ginro mistook the bloodstained Chen Yu for an enemy, so Chen Yu cut the Electric Light’s wire and attacked the villagers in the darkness.
• Chen Yu quickly defeated Ginro, Kinro, Kohaku, Magma, and others, then charged at Senku while Gen warned Kohaku.
• Kohaku intervened, but Chen Yu caught her kick and threw her aside before a light let Senku recognize him.
• Chen Yu imitated Tsukasa’s voice and threatened Senku with his spear, then revealed Suika and Mirai and explained his voice imitation.
• Chen Yu told the villagers they had failed to handle a sudden attack and began addressing their mistakes.

Chen Yu assessed the fighters’ weaknesses and proposed ways to improve their combat roles, then hinted that his side had a plan to end the war soon. Ukyo collapsed after inhaling a fragrance and was discovered by Chen Yu and the others.

• Chen Yu told Kohaku to improve her lower-body balance, advised Kinro to guard his back and practice spearmanship, and suggested Magma use armor or throw stones.
• Chen Yu gave the group cold-prevention pills and assigned roles, identifying Senku as a scientist and Gen as a deceiver suited to diplomacy.
• Chen Yu told Senku that the battle would end within three months and said he had a plan when Kinro asked whether they could win.
• Ukyo decided not to report Chen Yu’s intelligence to Tsukasa, but collapsed after realizing he had inhaled a strange fragrance.
• Chen Yu and the others arrived where Ukyo had fallen.

Chen Yu revealed that he planned to counterattack the Tsukasa Empire, and the villagers heard his preparations for a ceremony celebrating the Goddess and Diamond-sama. Hongye Yan infiltrated the village to investigate Ukyo’s disappearance, then fled after realizing she might have been spotted.

• Chen Yu explained that Ukyo had been knocked out by Bewitching Incense and carried him back while proposing a counterattack against the Tsukasa Empire.
• Senku reassured the others that Chen Yu had a plan, and everyone listened as Chen Yu outlined it late into the night.
• Hongye Yan returned to the place where Ukyo had disappeared and overheard villagers praising Diamond-sama and the Goddess while discussing a captured spy.
• Hongye Yan crept near Ishigami Village and overheard Gen, Magma, the Priestess, and others discussing Diamond-sama, the Goddess, and a sacrificial ceremony.
• Kohaku called out nearby, and Chen Yu ordered the others to prepare the ceremony and deal with the prisoner as Hongye Yan escaped with what she had learned.

Tsukasa ordered the Tsukasa Empire to scout Senku’s village and seize its divine maiden, then launched an all-out attack after the villagers staged a sacrificial ceremony. Chen Yu prepared the villagers to resist and warned them to avoid Hyoga and Hongye Yan if possible.

• Hongye Yan reported that Ukyo had been captured and that Senku’s village had a Lord Diamond, a divine maiden, and iron tools, so Tsukasa ordered his forces to scout for an opening and target the maiden.
• Senku checked the ceremony preparations with Chen Yu, who said the plan depended on someone coming through.
• At sunset, Kinro, Ginro, Magma, and other villagers performed an elaborate ceremony around a bonfire while Tsukasa and his forces watched from outside the village.
• Chen Yu, Senku, and Gen joined the ceremony, and a masked man whom Tsukasa identified as Diamond appeared beside the small figure presented as the divine maiden.
• After the ceremony ended, Tsukasa ordered an all-out attack, assigning Hyoga to fight the people he had identified and taking Diamond for himself.
• Chen Yu sensed the attackers and told the villagers to deal with the others, flee from Hyoga or Hongye Yan if they could, and use traps or numbers against stronger opponents.

Tsukasa invaded Ishigami Village to seize Chen Yu, while the villagers fought back and Diamond faced Tsukasa in an evenly matched battle. Tsukasa recognized the iron armor Chen Yu had made for Diamond and continued fighting as the two sides watched.

• Tsukasa entered the village and attacked Diamond, while Hyoga and Hongye Yan fought Kohaku and Kinro and the villagers used coordinated tactics to disable the invaders.
• Hyoga noticed that Shell Things affected people differently, dodged arrows from a masked figure, and found Kohaku and Kinro far stronger than before.
• Tsukasa and Diamond traded blows while questioning each other about Tsukasa’s plans and his demand for Chen Yu.
• The fighters gathered behind their leaders as Tsukasa and Diamond exchanged heavy attacks; Tsukasa hurt his foot when he kicked Diamond.
• Diamond revealed iron armor made by Chen Yu, then charged Tsukasa and resumed their punishing battle of attrition.

Chen Yu, disguised as Diamond, fought Tsukasa and then Hyoga as the village’s plan to end the conflict unfolded. Tsukasa recognized Mirai and turned toward Hyoga after Chen Yu was wounded.

• The day before the battle, Chen Yu explained a plan to lure Tsukasa and his followers into a trap, with the villagers assigned to distract or restrain them.
• As Tsukasa and Diamond reached the apparent end of their fight, Hyoga attacked from behind, but Diamond shoved Tsukasa aside and blocked the spear with hidden cardboard.
• Chen Yu revealed himself as Diamond, took the Sword Box Kohaku threw him, and battled Hyoga with its swords.
• Hyoga wore Chen Yu down and wounded him with a spear thrust, causing Tsukasa to react with growing anger.
• Mirai approached Tsukasa and took his hand, and Tsukasa removed the Goddess's helmet before walking toward Hyoga.

Tsukasa defeated Hyoga, reunited with Mirai, and made peace with Senku and Ishigami Village. As the Tsukasa Empire settled in, Tsukasa agreed to help revive humanity, while Chen Yu revealed he still held a grudge against certain people.

• Chen Yu withdrew so Tsukasa could fight Hyoga, while Senku and Gen treated Chen Yu's wounds and the villagers restrained Hongye Yan.
• Tsukasa beat Hyoga unconscious, and Chen Yu forced a pill into Hongye Yan's mouth and told him it was poison.
• Mirai ran to Tsukasa, who embraced her and thanked Chen Yu for bringing her back.
• Senku switched on the village lights, and Tsukasa and Senku shook hands to make peace.
• Tsukasa agreed to help Senku revive humanity but said he would stop certain people from being revived, and Chen Yu confirmed his grudge against them.