Kaidou/History

Childhood
Kaidou was born on the Grand Line 59 years ago. He resided in the Vodka Kingdom as a child, which invaded and looted other towns in order to be able to afford membership in the World Government and was considered its strongest soldier by the time he was 10 years old. Three years later, Kaidou started questioning this system and the king, not knowing what to do with him, decided to sell him off to the Marines in return for the right to attend the next Levely. However, Kaidou escaped from the battleship carrying him, and immediately received a bounty of 70,000,000. Kaidou allowed himself to be captured numerous times afterward for the purpose of eating the food on the battleships, escaping with ease once he had his fill.

Beginnings as a pirate


44 years ago, at the age of 15, Kaidou was on Hachinosu overwhelming numerous pirates in combat when he was invited by Edward Newgate to join the Rocks Pirates, under the command of Rocks D. Xebec. Upon being enlisted as an apprentice, Kaidou formed a sibling-like bond with a fellow crewmate, Charlotte Linlin, and proved to be a dominant force of the group. 38 years ago, the Rocks Pirates clashed with Gol D. Roger and Monkey D. Garp on God Valley and were defeated, resulting in the crew disbanding. On the day the Rocks Pirates fell, Linlin gave the Uo Uo no Mi, Model: Seiryu to Kaidou, putting him in her debt, which she considered to be a lifelong one.

Since becoming a pirate, he had been defeated only seven times and captured eighteen times by the Marines and the other members of the Four Emperors. In one of those occasions where he had been arrested, he was taken to Punk Hazard and imprisoned in the Third Research Institute, where Dr. Vegapunk was able to extract a sample of Kaidou's Lineage Factor, allowing the scientist to replicate his Devil Fruit, although the results were deemed to be unsatisfactory. At least 33 years ago, Kaidou escaped the facility and began building his own crew. While escaping, Kaidou encountered a young lunarian boy named Alber, who was held captive at Punk Hazard and experimented on by the World Government. After freeing him and demolishing the facility, Kaidou recruited Alber as his right-hand man, and noticing his extraordinary strength, gave him his epithet "King".

Kaidou was not recognized as one of the top pirates in the world until around the time when Roger was executed. He, along with Shanks, then joined Whitebeard and Big Mom among the ranks of the Four Emperors.

Wano and the rise to power
28 years ago, Kurozumi Higurashi approached Kaidou with an offer of territory to build weapons factories on in a nation known for its skilled craftsmen, allowing him to increase his might further. Kaidou agreed to this and began occupying Wano Country once Higurashi's relative Kurozumi Orochi had seized control of the shogunate; in exchange for the ability to grow his weapons enterprise, Kaidou served as a protector for Orochi. It was around this time that Kaidou had a son named Yamato, who was actually born as his daughter. Yamato later told him that he wanted to be Oden, and Kaidou beat him in response. 25 years ago, Kaidou confronted Kozuki Oden at the shogun's castle after the latter attempted to kill Orochi. Kaidou and Orochi then made a deal with Oden. If Oden danced naked in the Flower Capital once a week, citizens would be spared. They also promised to leave Wano in five years. Afterwards, Kaidou flew over the shogun's castle in his dragon form.



23 years ago, Kaidou fought with Gecko Moria in the Ringo region of Wano Country and defeated him. Though the exact details of the battle are unknown, Moria lost his entire crew and was left warped and shattered from the experience, holding a grudge against Kaidou to this day.



20 years ago, when Oden and his nine retainers were on their way to Onigashima, Kaidou and his crew confronted them in the Udon region. In the ensuing battle, Oden managed to inflict Kaidou with a permanent wound on his torso, possibly the first he ever received. However, Kaidou knocked Oden unconscious when Oden was distracted by Kurozumi Higurashi who had impersonated a kidnapped Momonosuke. Sometime after the battle, Kaidou killed Higurashi for her interference.

On the day of Oden's execution, Kaidou joined Orochi in witnessing the execution. Oden then made a deal with Kaidou to let those who survived the execution go free and Kaidou gave him an hour. Kaidou was amused to watch Oden as the latter endured standing in a pot of boiling oil while holding his retainers above his head with a board. Although Oden successfully survived one hour in the boiling pot, Kaidou and Orochi decided to execute Oden and his retainers regardless. As Oden's retainers fled, Kaidou apologized to him for Higurashi's interference before shooting Oden in the head.

After Oden's death, Kaidou attacked and set Oden Castle ablaze before Oden's retainers returned. While threatening Momonosuke, he told the boy that his father was a foolish lord. However, Kaidou decided to leave Momonosuke in the burning castle instead of killing him outright.

During that time, Kaidou also managed to get hold of a Road Poneglyph that was underwater thanks to Jack's fish-men nature.

Eventually, not long after Oden's death, Kaidou confronted a chained-up Yamato for using Haoshoku Haki to knock out many of his subordinates. He thought that his son's ability to use Haoshoku Haki was promising, but he still insisted that he should die for calling himself Oden. Kaidou decided to lock his son up inside of a cave in Onigashima for an entire month with a few other samurai. He placed a bunch of swords inside of the cave so that the samurai would fight for a single portion of food. Before leaving, he told his son that he wished all of this upon himself for calling himself Oden. After the samurai broke out of the cave, Kaidou was informed of this by his subordinates.

Ten years ago, the Kozuki Family's supporters, who feared that they would be too old and weakened to fight by the time the twenty years were up, gathered to stage a massive rebellion before the comeback of Oden's retainers. Kaidou personally intervened and brutally massacred a majority of the rebels along with their families. At some point after taking over Wano, Kaidou additionally faced the thief Shutenmaru.

About 3 to 4 years ago, Kaidou and his top subordinates were away from Onigashima on an expedition. The Spade Pirates invaded due this time period. When Kaidou returned, he was furious when he found his dragon statue destroyed.

Sometime within the last four years, Kaidou began collaborating with Warlord of the Sea Donquixote Doflamingo and the rogue Marine scientist Caesar Clown to create an army of artificial Zoan Devil Fruit users, via SMILE.

Marineford Arc
When Whitebeard was on his way to save Ace from his execution at Marineford, Kaidou alongside King tried to attack him. However, Shanks intercepted Kaidou before he could reach Whitebeard. It is unknown how their encounter ended, but Shanks arrived unscathed at Marineford by the end of the war.

During the Timeskip
At some point during the timeskip, the Drake Pirates as well as the On Air Pirates became Kaido's subordinate crews.

A few months ago, Orochi reveals to Kaido the return of the Nine Red Scabbards thanks to Toki's powers. Although Kaido didn't fully believe it at first, he stated that he wanted to ask them something about the background of the Kozuki clan, so he tells him to leave them alive. Here Orochi assures him that the spy's information is real and begins to tell him about the latter's past.

Dressrosa Arc


Kaidou went up to Ballon Terminal, where he encountered Urouge, who learned of his intention to attempt suicide and allowed him to proceed. Kaidou jumped off the sky island and landed 10,000 meters below on the Kid Pirates' base. However, he only received a minor headache and found himself face-to-face with the Kid, On Air, and Hawkins alliance. After cursing Whitebeard for having been able to die, Kaidou yelled that Doflamingo needed to make preparations for battle before promising to start a massive war due to the world boring him. Kaidou then offered the Kid Pirates and the Hawkins Pirates to join him, which the Kid Pirates did not accept. Kaido then easily defeated Eustass Kid and Killer, while Hawkins joined him.

Zou Arc


A After Jack's defeat, Apoo contacted Kaidou in his fortress, revealing that they had lost all contact with Jack's fleet after they went to attack Zou for a second time.

After learning that Jack's attempt to rescue Doflamingo failed, Kaidou was enraged at not being able to acquire any more SMILEs, which meant he could not gain any more Gifters. As he drowned his sorrows in alcohol, Kaidou's despair turned to rage when his subordinates mentioned Monkey D. Luffy and Trafalgar Law, causing him to smash one out of the building with his mace. Kaidou angrily stated that the two Supernovas were nowhere near him in power, pointing to the defeated Eustass Kid as an example.

Levely Arc
As the news of Luffy's exploits at Totto Land spread across the world, Kaidou read the newspaper and angrily wondered why Luffy was in Big Mom's territory. A few days later, he was contacted by Big Mom, who demanded the right to kill Luffy. He rejected her request since he wished to take care of Luffy himself, but Big Mom was unbending as she reminded him of a debt.

Wano Country Arc
After getting drunk, Kaidou flew to Kuri in Wano Country. On the way, he found Speed and Tama and attacked them after hearing a report of the former's treachery. He then went to Okobore Town and called out to Jack to bring Luffy and Law to him. While flying over Okobore Town, he recognized Shutenmaru and asked him to become his subordinate. Kaidou was drunk and in a partial stupor, which was a sight that unnerved even the likes of Jack, a subordinate known for his own violent streaks, fearing what Kaidou would do in this state. Basil Hawkins then came and told Kaidou that Luffy and Law were hiding in the ruins of Oden Castle, and Kaidou immediately flew toward it and shot a heat breath at it, instantly destroying it. However, he was then hit in the head by a giant punch from Luffy.



After Kaidou was sent crashing into the ground, Luffy got his attention by yelling at him. Kaidou attacked with a fire breath, but Luffy dodged and used Elephant Gatling. Kaidou then returned to human form, and Luffy activated Gear Fourth: Boundman and assaulted Kaidou with Kong Organ. Luffy's attacks were ineffective, as Kaidou then struck Luffy with Raimei Hakke, rendering him unconscious with just one hit. Kaidou stood over Luffy, scoffing at the idea his opponent aspired to be Pirate King after bringing him down with such ease.

Though Luffy was unconscious, Kaidou noticed that Luffy was still glaring at him. He then ordered his men to imprison Luffy, deciding to break his spirit and turn him into a subordinate. While walking away, Kaidou learned that Luffy possessed Haoshoku Haki when the latter instinctively knocked out some of his men. Kaidou found that attribute worth some credit but was equally quick to order Luffy locked up. Deciding to take care of Law later, Kaidou departed to go drink again, annoyed that he had sobered up.

When he heard that Big Mom and her crew were attempting to enter Wano, Kaidou ordered his subordinates to stop them. He then heard that King knocked the Queen Mama Chanter off the waterfall.

While Queen was at Udon, Kaidou informed him through a Smart Tanishi about Komurasaki's death. Kaidou then watched the broadcast of Shimotsuki Yasuie's execution.



After Big Mom was brought to Onigashima, Kaidou ordered his subordinates to release her from her cuffs. The two Emperors then began to argue and clashed weapons, causing the skies above Onigashima to split in two. The two Emperors continued fighting throughout the night. Kaidou and Big Mom eventually stopped their fight and came to an agreement. After speaking with Apoo about his return over Smart Tanishi, Kaidou announced to his subordinates that he and Big Mom were forming a pirate alliance to take over the world, shocking many who heard the unexpected news.

As the Beasts Pirates were preparing for the upcoming feast on the day of the Fire Festival, Kaidou asked for his son before he was informed of the Tobiroppo's arrival. Kaidou, King, and Jack then had a meeting with the Tobiroppo. After having Bao Huang go over the day's schedule, Kaidou gave the Tobiroppo the mission of finding his son Yamato, saying he would let them battle one of the All-Stars for their position if they succeeded.

Kaidou then enjoyed the festival with Orochi and did not mind if Black Maria decided to stay. They were briefly interrupted when Kanjuro arrived with Momonosuke. Kaidou told his men to stand down as Kanjuro was Orochi's ally. As Kanjuro delivered Momonosuke to Orochi, Kaidou expressed his disappointment with the boy. He also learned that the plot to stop the Kozuki rebellion failed and that Luffy, Roronoa Zoro, Kid, and Killer were present on the island.



He later went to the Performance Stage to announce a project dubbed "New Onigashima". He proceeded to explain his plans to find the Ancient Weapons and the One Piece and to transform Wano Country. When Orochi objected, Kaidou promptly decapitated him. He further explained that he planned to move his base to the Flower Capital, turn Wano into a pirate nation, and have Yamato become shogun. He also gave Orochi's subordinates a choice to join him or die. Out of self-preservation, Orochi's subordinates submitted to Kaidou. The Emperor then turned to Momonosuke and asked for his name, offering to spare him if he denied being Oden's son. After Momonosuke refused to lie, Kaidou was surprised when the Scabbards arrived and attacked him.

As Kaidou was pushed to the lower floor, the Scabbards managed to inflict wounds on him. While speaking to the Scabbards, Kaidou attempted to discourage them by stating that their pirate allies would betray them. After hearing Luffy's declaration of war, Kaidou transformed into his dragon form and flew to the roof of the Skull Dome with the Scabbards hanging onto him.

On the top of the dome, Kaidou commented on the Mink Tribe's ability to transform into their Sulong forms as he was joined by Jack, Nangi, and some Beasts Pirates when they prepared to fight the mink forces.



Jack suffered severe injuries from his fight with the Sulong minks, prompting Kaidou to step in before Jack could be killed. The Emperor then resumed his battle with the Scabbards. Kaidou tried scorching the samurai with a fire breath, but Kin'emon sliced the flames and cut Kaidou's mouth. Kaidou roared lightning at them, but they dodged around it, and each struck him in turn. Kaidou was confused on how their attacks could injure him. After Raizo reflected Kaidou's Bolo Breath back at him, four of the Scabbards—Ashura, Kin'emon, Denjiro, and Inuarashi—replicated Oden's Two Sword Style stance and struck Kaidou's scar with the same attack that made it.

While recovering from that attack, Kaidou remarked that he was reminded of Oden, but the Scabbards did not have the same strength as him. Kaidou then retaliated with a roar that created wind scythes, one of which sliced off Kikunojo's left arm. After Kin'emon cauterizes Kikunojo's wound, Kaidou returned to human form and praised the samurai for their determination. Continuing the battle, Kaidou gained the upper hand and began overwhelming the Scabbards and later incapacitated them.



Soon, Kaidou used his power to lift the entire island of Onigashima above sea level and began moving it to the Flower Capital. As the island was floating to its destination, Kaidou was joined by Big Mom, whom he provided fire and lightning for Prometheus and Zeus to feed on in order to recharge as Big Mom told him to leave Nico Robin alive. Kaidou asked if her daughter Charlotte Pudding can read the Poneglyphs, but Big Mom decided not to wait for her power to awaken. When she asked where he planned on dropping Onigashima, Kaidou told her that he would drop it on a castle in the Flower Capital that still stands as a symbol of the Kozuki. Big Mom started inquiring about the Road Poneglyph, causing Kaidou to tell her that her true intentions were showing. She replied that she still considered Kaidou as a little brother and reminded him that she was the one who gave him his Devil Fruit on the day Rocks fell, which she believed was Kaidou's life debt to her. He brushed her off and said they could talk more about it after they find the One Piece.



Later on, Kid, Killer, Law, Zoro, and Luffy arrived on the roof. After Luffy had spoken to the wounded Kin'emon and Law had teleported the Scabbards to a safe place, Kaidou attempted to attack Luffy, but Luffy dodged it and struck back with a powerful Gear Third punch that made Kaidou bleed, shocking both Emperors. Though initially stunned that Luffy's attack harmed him, Kaidou regained his composure and struck back with his club. Luffy managed to avoid the full brunt of the attack but was still grazed. However, Kaidou was still impressed that Luffy did not go down easily. After Big Mom attempted to attack Luffy, Kaidou launched another attack on the Straw Hat captain, but Law teleported Luffy to another spot. Kaidou then told Big Mom to step back as he wanted to see the strength of the five members of the Worst Generation. Zoro, Killer, Luffy, Kid, and Law then unleashed their own attacks on Kaidou, but the Emperor transformed into his dragon form and joined Big Mom in the sky.

Kaidou used Kaifu to unleash several wind blades on the five members of the Worst Generation, but they managed to avoid the blades. Luffy got close to Kaidou and struck him with Gomu Gomu no Kong Rifle, which injured him. Kid moved underneath Kaidou and grabbed his head with his robot, before slamming him into the roof with Slam Gibson, which also caused him pain. Law maneuvered around Kaidou with his powers and tried to attack his heart with Gamma Knife. Kaidou shook them off and admitted that they had learned how tough his defense was. Killer started running along Kaidou's body and used Kamaa Sonic to damage him from the inside. However, Killer got struck by Big Mom's Indra. While Killer was falling, Kaidou tried to chomp on him, but Luffy kicked him away with Gomu Gomu no Rhino Schneider. Kaidou prepared to use Bolo Breath on Luffy, but Zoro had Law teleport him to in front of Kaidou so he could cut Kaidou's flames. Zoro then attempted to attack Kaidou with Enma, but Zoro missed his attack and ended up cutting off one of the horns of the Skull Dome, while Kaidou tried to figure out why Oden's presence could be felt in that sword. After Big Mom used Tenman Daijizai Tenjin on the opposing pirates, Kaidou hit Luffy with Bolo Breath, but to Kaidou's surprise, Luffy came out unscathed, claiming that it was his guts that protected him. He then struck Kaidou with Gomu Gomu no Kong Gatling.

After the pummeling he received from Luffy, Kid and Killer tried to continue on the offensive, but Kaidou stopped them by creating some twisters. Luffy, who got worn out from using Gear Fourth, got caught in the wind. As Kaidou chomped on Luffy, Zoro used all three of his swords and sliced through Kaidou's scales. After recognizing Enma, Kaidou once again launched wind blades at the five Supernovas. Enjoying the battle, Kaidou later transformed into his hybrid form.

As the fight raged on, Kaidou and Big Mom kept facing against the bloodied members of the Worst Generation, with him complimenting Luffy for keeping the light on his eyes. Per Big Mom's suggestion, they both attacked simultaneously with the Hakai move against the Worst Generation only for Zoro to momentarily block it, which resulted in him getting a lot of damage and a part of the Skull Dome getting destroyed. As Luffy tried to attack Kaidou, they both faced off in heated battle where both tried to land a hit on the other, which would eventually result in Luffy getting knocked out again.



As Big Mom was about to fall to the sea, Kaidou attacked Zoro so that Prometheus could go help her, only to be suddenly attacked on the neck with an Injection Shot from Law, with Kaidou retaliating for it afterwards. Looking at Luffy, Kaidou laughed at him for glaring at him for a second time while still unconscious, and then mockingly asking Zoro or Law whether he should crush Luffy's eyes, brain, or heart. Before Kaidou could do anything to Luffy, Zoro attacked with Ashura Bakkei: Moja no Tawamure. Although Kaidou remained standing, he received a permanent scar due to Zoro's usage of Haoshoku Haki. As he prepared to finish Zoro off, Law tried to interfere, so Kaidou struck both with Raimei Hakke and was disappointed that they could have conquered the world if they had joined his crew.



Luffy stood back up and rebuffed the sentiment. After Luffy admitted to figuring out how Kaidou infused Haoshuku Haki into attacks, Kaidou confirmed that only a handful of people were able to do it, including him. He then prepared to strike Luffy again with his club, but Luffy blocked the attack and then struck Kaidou repeatedly without making any contact, eventually knocking the Emperor down to the ground. After Kaidou got back up, he told Luffy that he seemed to be enjoying this fight with him because he kept smiling when the risk kept increasing. With this, both captains resumed their fight, clashing with each other through Haoshoku Haki-infused strikes. Despite Luffy's new ability, Kaidou was still able to defeat him and knock him off the roof of the castle, regretting that he was unable to give Luffy a clear, sure death as proof of victory while cryptically stating that Luffy was not Joy Boy.



Being alerted by Bao Huang about Momonosuke's current location, Kaidou ordered her to announce his victory through Onigashima while he chased after Momonosuke himself through the hole Big Mom had made on his castle beforehand. Kaidou eventually found Momonosuke with Kin'emon in the first-floor attic and prepared an attack coated in Haoshoku Haki, striking through Kin'emon's swords as Momonosuke cried for the latter while being carried off by Shinobu. Kin'emon barely survived the attack and hopelessly attempted to buy some time, only for Kaidou to impale him on the ground. Kaidou then pursued Momonosuke and Shinobu to the edge of Onigashima, cornering them, but before he could kill the boy, Shinobu used her ability to escape the floating island by breaking the portion of land they were on.

Kaidou then heard Yamato calling him out from the top of the Skull Dome, ready to fight him. Kaidou transformed back into his dragon form and flew back to the rooftop. There, he mocked Yamato for attempting to rebel against him, insisting that he should give up and become shogun of Wano as he had planned. Yamato rebuffed Kaidou's intentions once more and declared allegiance to Luffy, stating that the latter would be the one to beat him and throw the Emperor out of Wano. With that, Kaidou transformed into his Human-Beast form and clashed with Yamato.



Kaidou began to emphasize how useful Yamato will be to his future arsenal. After Yamato attacked him in his hybrid form, Kaidou revealed that he went through great troubles to obtain the Inu Inu no Mi, Model: Okuchi no Makami, but he never intended on Yamato eating it. The father and son pair then faced each other in both of their hybrid forms. He began to further stress how incredibly valuable Yamato's fruit was, and that it was a shame to let a wannabe Oden eat it. While he exchanged more swings with Yamato, he claimed that the devil fruit was the guardian deity of Wano, so Yamato would have to protect Wano for Kaidou. As Yamato rejected the idea, Kaidou indicated that even though Orochi was Wano's tyrant, he still transformed the country into a weapons factory, a favorable action for Kaidou. As Kaidou rejected the idea of Yamato helping the samurai and freeing Wano, he attacked his son with Bolo Breath, which clashed with Yamato's own icy breath, creating a swirl between them.



After fighting for some time, Kaidou attacked his son with powerful flying strikes. Kaidou then confirmed that he was attacking Yamato with the intent to kill him. He said that because he bore the heavy burden of calling himself Oden, he must be prepared for an all-out war and not just a family squabble. After Yamato confronted him over why he stole Yamato's as well as Wano's freedom, he declared that there were no easy answers in this world. Then, they both attacked each other with Raimei Hakke, creating a clash of advanced Haoshoku.

As soon as Yamato's Kagimiyama cracked, they both repeatedly struck at each other with their Kanabo's, with Kaidou expressing that Yamato's attempts at gaining friends and allies were all in vain, due to his origin as his child before gaining the upper hand and furiously striking at him with his Kanabo. When Luffy and Momonosuke appeared in the sky above Onigashima, Kaidou was struck by a simultaneous punch from both Luffy and Yamato, forcing him to turn into his dragon form, being amused by their attacks while also expressing his surprise at Momnosuke's adult dragon form and explaining that the world does not need two dragons.

When his Boro Breath was dodged by Momonosuke, he was punched by Luffy with a Gomu Gomu: King Kong Gun, then followed by Momonosuke biting him in his torso, resulting in him expressing pain. Before he could counterattack, he was once again hit by Luffy and decided to transform into his Hybrid-Form. Both then infused their Haki and attacked each other, creating another clash of Advanced Haki, which even split the sky above Onigashima, revealing the full moon previously hidden. After the clash cooled off, Kaidou then turned his attention to Momonosuke, who was afraid of the height he was experiencing, attempting to finish him off for good this time, only to be blocked by Yamato again and soon afterwards by Luffy, who held him strain with his legs and asked Yamato to leave Kaidou to him. As the island was approaching the Capital, Kaidou's Flame Clouds were losing their power, leaving the island slowly crumbling, and both Kaidou and Luffy continued to clash with each other, trading blows with each other before Kaidou was knocked back by Luffy's Gum-Gum Roc Gun, with Luffy simultaneously falling back. However, both quickly got up, started laughing and commented on the fight finally becoming fun. Kaidou would then start drinking alcohol after returning to his normal form, to Luffy's annoyance, but clarified to Luffy that he is doing it to become stronger as he finally acknowledges Luffy's power.



When Luffy attempted to strike at Kaidou, the latter went through several stages of a special state called Shuron Hakke due to his alcohol consumption. In his Warai Jogo state and upon transforming into his hybrid form, he dealt a severe blow to Luffy with Ragnaraku that created a large crack in the roof of Onigashima. Kaidou entered the Ochikomi Jogo mode in his dragon form and lamented over not being able to protect Onigashima and the time it would take to rebuild it, before using Tatsumaki Kaifu on an approaching Luffy. He then shifted to his Naki Jogo state and returned to hybrid form, crying as he prepared to use Raimei Hakke on Luffy. However, Luffy was successful in dodging this attack and landed a reverse Haoshoku-infused kick on Kaidou's chin. The Emperor, still crying profusely, grabbed Luffy's leg with his tail and attempted to headbutt him. The two combatants had a headbutt clash powered by Haoshoku Haki, with their foreheads not touching. Kaidou won out the clash as Luffy remarked that Kaidou's haki was growing stronger as he was sent reeling. Kaidou then entered the final stage of Shuron Hakke, Okori Jogo and angrily fired off two Boro Breaths before he met Luffy's Roc Gatling with Gundari Ryuseigun. However, during the flurry of attacks, Luffy blocked a swing of Kaidou's Hassakai with Haoshoku Haki and managed to strike the Emperor's abdomen with a Haoshoku-infused kick bolstered by Gear Second and Gear Third, seemingly damaging Kaidou significantly.

When Big Mom was defeated, the two pirates were in the midst of a clash of haki-infused attacks, with Luffy being pushed back. Sensing that Linlin lost her battle, Kaidou emitted his Haoshoku Haki in rage, though Luffy was impressed that Law and Kid managed to win. Kaidou then recalled how the two first met, before entering his Naki Jogo mode and bursting into tears, though Luffy responded by entering Gear Fourth: Snakeman, and barraging Kaidou with Gomu Gomu no Hydra, stating that Kaidou's ambition meant nothing to him, how this was his final Gear Fourth, and how he wasn't stopping till he drove the King of Beasts out of Wano.



Kaidou was seemingly unable to respond to the omni-directional Hydra attack and contemplated on how such an attack should be impossible due to the innate nature of rubber, as he slowly transitioned to his Amae Jogo mode. Kaidou manages to escape the attack, using Nusubito Jogo and advanced Kenbunshoku, before transforming into his full beast form, grabbing Luffy in his mouth and flying high into the sky. He then let go of Luffy before firing a point-blank Boro Breath straight down, which blasted the Straw Hat captain all the way through Onigashima. Luffy managed to escape the attack by transitioning into his Boundman form and flying back to the top of the island. He then got above Kaidou and landed a Gomu Gomu no Over Kong Gun on the Emperor, which disrupted the Boro Breath the dragon was preparing to fire. However, Kaidou quickly recovered, entering his hybrid form and using Satsuriku Jogo mode to floor Luffy with Hourai Hakke. With Luffy resolving to end this with one final hit, he quickly bounced back and charged at the Emperor with another Over Kong Gun, with Kaidou dashing at him whilst preparing another Hourai Hakke. However, the bowler hat CP0 agent suddenly appeared and locked Luffy's attacking arm by grabbing on to it and using Tekkai, allowing Kaidou to knock the Straw Hat captain down. The CP0 agent escaped the strike, releasing just before the Emperor hit, whilst Kaidou could only attack in despair, as he relived another exciting battle being sabotaged by outside influence, just like during his duel against Oden. In response, Kaidou brutally attacks the CP0 agent.

Kaidou returned inside the castle in his dragon form, where he declares that Luffy is dead and demanding Momonosuke surrender to him, while also agreeing to fight anyone who still wishes to challenge him. He decrees that when Onigashima will drop on the Flower Capital, he will put everyone who lives in Wano to work producing weapons, and if they die, he'll find suitable replacements. He tells the samurai that their defiance against him incurred his wrath, and the price of failure is the loss of their freedom and hope, but until Momonosuke presents himself to him, he won't stop fighting. However, he soon hears what seemed to be the beating of a drum, before being grabbed by a huge hand and dragged silly back to the top of the roof by Luffy, who had awakened his Devil Fruit. Luffy proceeds to swing Kaidou around before slamming him on the ground. Luffy lets him go and Kaidou confesses how happy he is that Luffy survived before firing a Boro Breath at him. To his shock though, Luffy reflects it back at him and it blows up in his face. He recovers and apologizes to Luffy for allowing CP0 to interfere with their duel as the two prepare for their final fight.

While watching Luffy bouncing up and down, Kaidou told him he awakened his Devil Fruit since he was turning the ground into rubber like himself, yet he felt like the transformation was akin to that of a Zoan fruit, which confused him. Nevertheless, he bit down on Luffy and swallowed him, only for Luffy to bounce around in his insides before using Gomu Gomu no Fusen to inflate both his and Kaidou's body, causing him discomfort as the two floated up into the sky. Kaidou tried to figure out how Luffy was able to make his body being like rubber just as Luffy was about to stretch his arms through Kaidou's eyes to launch himself out of Kaidou's body using Gomu Gomu no Dasshutsu Rocket which caused additional discomfort to Kaidou. Luffy then launched himself higher into the air and made himself a giant to step on Kaidou, but Kaidou evaded and chomped down on Luffy's torso, but Luffy grabbed his head and tail and started using him like a jump rope until Kaidou used Boro Breath to blast him far away. As Luffy recovered and ran back to him, Kaidou changed into his hybrid form and struck Luffy with Kosanze Ragnaraku, slamming his head through the roof, causing everybody in the Live Floor to have their eyes popped out. As Luffy pulled his head back, Kaidou remarked that their fight looked like something out of a picture book but believed Luffy is at the end of his rope, which was confirmed when his awakened state wore off. Though Kaidou himself fell to one knee, he told Luffy that after he died, he will tell everyone how valiantly he fought, but Luffy rejected this notion and changed back, assuring Kaidou that he was not afraid of dying. Kaidou managed to slam Luffy with Hassaikai a few times before Luffy bounced off a rock at Kaidou while spinning his arms like a propeller. Kaidou tried to block his attack while also trying to figure out what Luffy's power was, claiming no one is capable of taking him down, only to get punched straight through the face by Luffy and knocked onto his back.

Kaidou picked himself back up and asked Luffy who he was to which Luffy answered that he is the one who will surpass him and become the Pirate King. Kaidou acknowledged that Luffy still hasn't lost his spirit and how ridiculous his power was. He admitted he has lost a lot in this war, but believed Luffy has too, only for Luffy to retort that he will take it all back. He used Gundari Ryuseigun on Luffy but got hit multiple times by Luffy as well, whose punches stretched through him again. He then noticed smoke coming from the bottom of the roof and believed that the whole castle is on fire, and everyone will burn to death, but Luffy responded that he trusts his friends to handle the problem as Kaidou fired a Kaifu attack that Luffy dodged. He then watched as Luffy grabbed a bolt of lightning with a smile on Luffy's face.

Luffy used Gomu Gomu no Kaminari to throw the bolt of lightning at Kaidou, but he sidestepped and slammed Luffy from the side, sending him flying far away again. Luffy used another lightning bolt to propel himself back to attack Kaidou again, but he quickly dodged the attack and struck Luffy on the head. As he did so, he told Luffy that having a strong Devil Fruit isn't enough to conquer the seas; Roger himself didn't have one yet he still became the Pirate King, and Kaidou said that such hurdles can only be overcome with Haki as he hit Luffy with Daiitoku Raimei Hakke, knocking him into the air again. However, Luffy grabbed Kaidou while being past the storm clouds and Kaidou tried to shake Luffy off, first by hitting his arm with Hassaikai, then changing into his full dragon form to hit him with Tatsumaki Kaifu and Boro Breath. His efforts were futile, as not only did Luffy hang on, but inflated his other fist to a humongous size with which to finish off Kaidou.



Seeing Luffy's giant fist, Kaidou decided to take it head on as he enveloped himself in fire, which finally caused Luffy to let go of him, a move Kaidou said was the right call. He told Luffy that Oden was burned to death and ever since then, the people of Wano desperately clung onto the hope their "savior" would come. He also told Luffy that his fist would never hit him because his fire would vaporize it, and he met Luffy's Gomu Gomu no Bajrang Gun with his Shoryu: Kaen Hakke. As they clashed, Kaidou commended Luffy for coming so far but believed he could not change the world. Kaidou did ask, though, what kind of world Luffy wanted to create, and Luffy answered that he wanted to make a world where his friends could eat as much as they want. Kaidou then remembered a conversation he had with King once, in which he stated that Joy Boy would be the one who was able to defeat him. Luffy's fist pushed through Kaidou's attack and punched him so hard in the face that it broke off his left horn and sent him crashing deep into the ground.

Rendered unconscious, Kaidou reverted back into his human form and plummeted into Wano's magma chamber, where Big Mom had also fallen. As a result, an underwater volcano erupted from where Onigashima had previously sat, with both Emperors, presumably, getting caught up in the explosion.