Kaido

Biodata

Power Progression

Background

Kaido was regarded as a monster from childhood. By age ten, he had become the strongest warrior in the Vodka Kingdom and possessed enough power to destroy a nation alone. A year before his introduction, his kingdom’s king sold him to the Marines in exchange for Reverie participation rights, but Kaido escaped. His betrayal and escape closely parallel Oak’s own past. 3

He joined the Rocks Pirates four days before Oak and immediately invoked that seniority to call himself Oak’s “big brother.” Their first exchange instead began a prolonged rivalry. 10

During his early years with the Rocks Pirates, Kaido was one of the crew’s two apprentices alongside Oak. Although he initially regarded Oak as an upstart rival, repeated defeats, shared expeditions, and their mutual survival during the God Valley Incident turned their relationship into a fiercely loyal and abusive brotherhood. 10 15 161 185

At God Valley, Kaido ambushed Charlotte Linlin and stole the Fish-Fish Fruit, Mythical Zoan: Azure Dragon Form from her. The fruit gave him the power he had long desired and became the foundation of his later reputation as one of the Four Emperors. 181 182 264

After Rocks formally disbanded the Rocks Pirates during the God Valley Incident, Kaido refused to let other former crewmates recruit Oak away from him and wished to establish the strongest violent pirate crew alongside him. Oak declined, and Kaido subsequently rose independently as an Emperor. 209 211 264

Thirty-six years after Oak was publicly declared dead, Kaido immediately abandoned Wano upon recognizing evidence that Oak had returned. Their reunion began with Kaido attempting to reverse their old hierarchy, only for Oak to defeat and humiliate him so thoroughly that Kaido again accepted Oak as his “Big Brother.” 353 361 366 367

Later reports of Oak’s overwhelming victory over the Red-Hair Pirates convinced Kaido that Oak had held back throughout their reunion battle. Despite the blow to his pride, Kaido answered Oak’s summons to the New World and became the first former crewmate to pledge his pirate crew to Oak’s new alliance against the World Government. 453 465 475

Appearance

At fifteen, Kaido was over seven meters tall, though still lean compared with his later build. He had a clearly defined muscular frame and commonly carried a spiked club. 10 12

By the current era, Kaido possesses the colossal, heavily built physique associated with his status as an Emperor. His body is further enhanced by the Azure Dragon Mythical Zoan, allowing him to assume a massive dragon form and a horned hybrid form covered in azure scales. 315 363 364

• Over seven meters tall, making Oak appear child-sized beside him during their apprenticeship. 10 12
• Lean but visibly muscular during his apprenticeship. 10
• Referred to as a “horned rookie” during his time in the Rocks Pirates. 19
• Possesses a far bulkier adult body and an exceptionally resilient physique. 315 364
• Uses a large spiked club or kanabo as his primary weapon. 10 12 315
• In Azure Dragon form, becomes an enormous blue dragon capable of flight. 182 185
• In hybrid form, retains his human agility while gaining azure scales, a dragon tail, fangs, and increased physical power. 363

Personality

Kaido is fiercely proud, particularly about his strength and standing. Being knocked out of Rocks Pirates headquarters by Oak in front of Hachinosu’s pirates enrages him more than the injury itself, and he refuses to accept defeat to someone his own age. 11 14

He favors direct violence over planning. When Rocks discusses recruiting Harald and locating the Great Hammer Warband, Kaido proposes subjugating them through force; Rocks responds by kicking him in the face. 18 However, Kaido is not entirely reckless: he avoids challenging Rocks when he knows he would lose and listens closely when Newgate explains Conqueror’s Haki Infusion. 21

His rivalry with Oak combines resentment, competitiveness, and an increasingly brotherly familiarity. The two repeatedly fight, insult one another, and exploit each other, yet continue training and traveling together. 22 26

Kaido is unusually loyal beneath his violent and self-serving exterior. He volunteered to aid Oak and Newgate against Admiral Kong when other Rocks Pirates chose to watch, protected Oak from Garling’s sneak attack, and remained concerned that he had not been present when Ochoku ambushed Oak. 60 162 122

He is also intensely impulsive. His desire to confront Ochoku caused him to rush alone into a Marine trap, where Garp, Sengoku, and Zephyr captured him with Seastone. 250

Although Kaido spent decades as one of the Four Emperors and initially believed that his adult strength surpassed Oak’s, his former fear and conditioning resurfaced during their reunion. After Oak beat him into submission, Kaido willingly resumed calling him “Big Brother,” while still retaining his usual violent temper and desire for battle. 361 362 366 367

Kaido remains eager to challenge powerful enemies and overthrow the World Government. After learning of Oak’s conflict with Imu, he immediately proposed attacking Mariejois, only for Oak to reject the plan as suicidal without the support of their former allies. 367

Learning that Oak had held back against him at Thriller Bark left Kaido drunk, dejected, and prone to taking out his frustration on Jack. His delight at the defeat of rival pirates nevertheless persisted, and he later eagerly joined a brawl involving Oak, Newgate, and Shiki. When Oak proposed an alliance and a world-spanning war, Kaido was the first to offer his support. 453 472 475

Abilities & Skills

Physical Strength and Durability

Kaido possesses exceptional natural strength, endurance, and toughness even before obtaining a Devil Fruit.

• His raw strength is comparable to Oak’s during their first duel. 12
• Fights Oak continuously for a full day and night without food, water, or rest. 14
• Endures Oak’s Hasshoken strikes, building-level impacts, and repeated blows while continuing the battle. 13
• Oak’s later Vampire Fruit can bypass Kaido’s physical defenses by draining blood and lifespan, demonstrating that his durability does not protect him from rule-based abilities. 31
• As a teenager, he survived strikes from Garp, Kong, and Garling despite being physically outmatched by them. 60 160 162
• His adult body, Azure Dragon Mythical Zoan, and Indestructible Diamond Body make him exceptionally difficult to injure even for Emperor-level opponents. 364 366
• He can endure direct attacks from Oak, including Conqueror’s Haki-infused blows and sword strikes, though Oak’s overwhelming power can still break through his defenses. 361 364 366

Azure Dragon Devil Fruit

Kaido consumed the Fish-Fish Fruit, Mythical Zoan: Azure Dragon Form at God Valley after ambushing Linlin and stealing the fruit from her. The ability grants him immense physical enhancement, aerial mobility, dragon transformations, and elemental attacks. 181 182

• Can transform into a colossal Azure Dragon and fly freely through the sky. 182 185
• His dragon form enabled him to transport and support several powerful allies during the God Valley Incident. 209
• Can unleash Bolo Breath, an enormous blast of destructive dragon fire capable of vaporizing a mountain. 257 315
• Can create destructive wind-based attacks, including Wind Scythes and Tornado Demolition. 361 363
• His hybrid form combines human agility with dragon physiology and represents his strongest ordinary combat form. 363
• The fruit dramatically improved his strength, durability, mobility, and confidence, though it did not allow him to surpass Oak. 182 185 361

Armament Haki

Kaido had already learned Armament Haki by the time Oak joined the crew.

• Coats his spiked club in Armament Haki to increase its striking power and durability. 12
• Uses the coating at more than full strength during the final stage of his duel with Oak. 14
• His Haki-reinforced club withstands Oak’s Extreme Impact, which would otherwise have shattered it. 12
• Reinforces his body and weapons with Armament Haki in his Emperor-era battles. 361 363 365
• Uses a heavily Armament Haki-coated forehead while performing Rising Dragon: Flame Bagua. 365

Observation Haki

Kaido possesses advanced Observation Haki by adulthood.

• His combat awareness allowed him to contest highly technical fighters such as Zephyr despite being repeatedly struck at vital points. 55
• Can predict the future, though Oak’s superior future sight prevented Kaido from perceiving or evading Oak’s movements during their reunion. 361
• His advanced Observation Haki allowed him to anticipate and deflect many of Garling’s attacks during their God Valley battle. 162

Conqueror's Haki

Kaido possesses Conqueror’s Haki, which matches Oak’s in their early clash.

• His Conqueror’s Haki collides evenly with Oak’s, producing black lightning and knocking nearby pirates unconscious. 13
• He seeks to learn Conqueror’s Haki Infusion under Newgate alongside Oak. 21 22
• After a month of harsh training, he has not yet mastered infusion. 22
• Channeled his Conqueror’s Haki into the joint attack Apocalyptic Abyss with Oak, allowing the technique to injure Garp. 161
• By the current era, he can coat his kanabo in Conqueror’s Haki and clash at a level capable of splitting the sky. 363 364
• Uses Conqueror’s Haki-infused techniques including Three Realms: Ragnaraku, Kundali Dragon Swarm, Drunken Thunder: Naraku, and Rising Dragon: Flame Bagua. 362 364 365

Thunder Bagua

Kaido’s signature club technique was already developed during his apprenticeship and remains one of his primary attacks as an Emperor.

• Launches an extraordinarily fast Armament Haki-coated club strike. 12
• Forces Oak to block with a kick rather than evade outright. 12
• Used the technique against Garp, Garling, Eagle, and Oak across multiple eras. 160 162 315 362
• Can augment the technique with his Azure Dragon powers and Conqueror’s Haki. 362

Dragon Techniques

Kaido has developed numerous attacks through the Azure Dragon Fruit and his kanabo-based fighting style.

• Bolo Breath — A massive blast of dragon fire capable of devastating mountains and warships. 257 315
• Wind Scythes — Razor-sharp wind blades launched in dragon form. 361
• Tornado Demolition — A hybrid-form tornado of lightning and cutting wind blades. 363
• Three Realms: Ragnaraku — A Conqueror’s Haki-infused kanabo strike. 362 363
• Kundali Dragon Swarm — A barrage of Conqueror’s Haki-coated club attacks that creates an inescapable attack zone. 364
• Drunken Thunder: Naraku — A lightning-charged, Conqueror’s Haki-infused kanabo strike used while intoxicated. 365
• Rising Dragon: Flame Bagua — Kaido’s strongest technique, in which he coats his dragon form in Haki and charges forward with sufficient force to smash through and vaporize islands. 365

Drunken State

Alcohol significantly enhances Kaido’s combat ability.

• When intoxicated, his strength and speed increase substantially. 365
• Oak recognizes that Kaido becomes more dangerous after drinking and deliberately waited for him to become drunk during their reunion battle. 365
• Uses Drunken Thunder: Naraku while in this state. 365

Combat Instincts

Kaido adapts quickly in battle despite his impulsive temperament.

• After Oak’s opening punch catches him off guard, he blocks Oak’s next flying kick with his club. 11
• Recognizes Oak as a serious opponent after his Armament-coated strikes fail to overcome Oak’s defenses. 12
• Searches for a Devil Fruit capable of closing the growing gap between himself and Oak. 32 35
• Fought Zephyr despite the latter’s superior Six Powers technique and learned to rely on his durability against attacks aimed at his vital points. 55
• Adapted his Conqueror’s Haki for use in Apocalyptic Abyss despite not initially mastering Conqueror’s Haki Infusion independently. 161
• His adult combat style combines overwhelming durability, powerful Haki, dragon abilities, weapon skill, and future sight. 361 363 365

Equipment

• Spiked club / kanabo — Kaido’s primary weapon, used for Thunder Bagua, Three Realms: Ragnaraku, Kundali Dragon Swarm, and other Haki-infused attacks. Oak shatters his original club during their duel; Kaido later obtains replacements. 12 14 17 364
• Wine gourd — A large gourd carried at his waist. Kaido drinks from it to enter his enhanced drunken combat state. 365

Relationships

• Oak — Fellow Rocks Pirates apprentice, rival, recurring source of humiliation, and eventually Kaido’s acknowledged “Big Brother.” Kaido initially claims seniority over Oak, but Oak defeats him, repeatedly calls him “little brother,” charges massive tavern bills to him, and later overwhelms him after obtaining the Vampire Fruit. Their constant clashes develop into an antagonistic brotherhood. Kaido repeatedly defends Oak in critical situations, while Oak remains protective but regularly exploits, disciplines, and humiliates him. After realizing Oak held back during their reunion fight, Kaido nevertheless answers his summons and becomes the first to pledge a crew to his new alliance. 10 15 17 22 32 60 162 122 361 367 368 453 465 475
• Rocks D. Xebec — Former captain of the Rocks Pirates. Kaido fears neither confrontation nor punishment, but Rocks decisively asserts authority over him, including kicking him for proposing to subjugate Harald by force. Rocks later celebrates Kaido’s acquisition of the Azure Dragon Fruit and orders him to escape during the God Valley Incident. 18 19 185 209
• Edward Newgate — Senior crewmate, instructor, and paternal figure. Newgate retrieves Kaido for the Rocks Pirates, trains him and Oak in Conqueror’s Haki Infusion, fights beside him against Kong, and offers to give Kaido a Devil Fruit at God Valley without demanding repayment. Decades later, they join Oak’s Pirate Alliance, though Newgate and Shiki also turn on Kaido during a playful brawl with Oak. 4 21 22 60 174 472 475
• Charlotte Linlin — Former crewmate and creditor. Kaido stole the Azure Dragon Fruit from her at God Valley after she intended to give it to Perospero, leading her to demand that he repay the resulting lifelong debt. 22 26 181 198
• Ganzui — Restrains Kaido when he attempts to attack Rocks in anger. 19
• Garp — One of Kaido’s earliest and most humiliating powerful opponents. Garp defeated the teenage Kaido with a single punch, but Kaido and Oak later injured him with Apocalyptic Abyss. 160 161
• Saint Garling — God’s Knight whom Kaido fought at God Valley after intercepting Garling’s sneak attack against Oak. Kaido’s raw toughness and physical strength exceeded Garling’s, but Garling’s Immortal Body prevented a quick victory. 162
• Eagle — A recurring Marine challenger whom Kaido allows to survive because of Eagle’s connection to an old companion. Their repeated battles are driven by rivalry and mutual recognition of strength. 315 316
• Yamato — Kaido’s imprisoned child, who views him as an oppressor and hopes for powerful outsiders to defeat him. 315
• King and Queen — Kaido’s senior Beasts Pirates subordinates. King worries that Kaido’s repeated sparing of Eagle may create a future threat, while Queen understands Kaido’s old connections and explains his restraint. They avoid entering Kaido’s chambers during his drunken tantrum over Oak’s strength. 315 316 453
• Jack — Beasts Pirates subordinate who brought Kaido evidence of Oak’s return. Kaido later unjustly beats him while venting his frustration over Oak’s overwhelming strength and the Beasts Pirates’ failure to dominate rival Emperor crews. 353 453
• Gecko Moria — A former rival whose spirit and strength declined after Kaido defeated him. In the current era, Kaido brutally beats Moria for mocking him until Oak intervenes. 367
• Shiki, Captain John, and other former Rocks Pirates — Kaido retains lasting bonds with several former crewmates, though he recalls being attacked or bullied by many of them after arrogantly acquiring the Azure Dragon Fruit. He later joins Oak, Newgate, and Shiki in a chaotic sparring match and enters Oak’s alliance alongside Newgate and Shiki. 368 472 475

Story Role / Major Arcs

Recruitment and Duel with Oak

After joining the Rocks Pirates four days before Oak, Kaido attempts to establish himself as the senior apprentice. Oak immediately attacks him, beginning a public duel watched and wagered on by the crew and Hachinosu’s pirates. 10 11

Kaido displays Armament Haki and Thunder Bagua, while Oak relies on raw toughness, Hasshoken, and eventually newly awakened Armament Haki. After fighting for a full day and night, Kaido is defeated and dragged from the ruins unconscious by Oak. 12 14 15

Training Under Newgate

Kaido joins Oak in seeking Conqueror’s Haki Infusion. Newgate explains that the technique must be learned through personally enduring infused attacks, then trains both apprentices with the flat of his Haki-coated Murakumogiri. Neither achieves mastery after a month. 21 22

Punk Hazard and Ancient-Ruin Expeditions

Kaido accompanies Rocks, Oak, and Newgate on the restricted Punk Hazard mission after Oak warns of a possible traitor within the crew. He supports Oak’s suspicion of betrayal but is stopped from accusing Ochoku without evidence. 26

He later accompanies the group to the Sleeping Ancient Town and Asuka Island. Oak’s acquisition of the Vampire Fruit and Seven Star Sword leaves Kaido increasingly anxious to obtain a powerful Devil Fruit of his own. 30 32 35

Marine Encirclement

During the Marines’ large-scale encirclement, Kaido eagerly volunteers to fight the deployed Elbaf giants. Because he cannot fly at the time, he asks Oak to accompany him. 46

Kaido later fights Headquarters Ensign Zephyr during the same broader conflict. Although Kaido possesses all three forms of Haki, Zephyr’s refined Six Powers, speed, and precision repeatedly overwhelm him, demonstrating the limits of Kaido’s early combat technique. 54 55

He subsequently proves his loyalty by joining Oak and Newgate against Admiral Kong. Oak immediately uses him as a shield to recover, but Kaido survives Kong’s attacks and coordinates with Newgate to pressure the admiral. 60

God Valley Incident

At God Valley, Kaido sought a powerful Devil Fruit to overturn Oak’s dominance. After Linlin obtained the Fish-Fish Fruit, Mythical Zoan: Azure Dragon Form, Kaido ambushed her, knocked the fruit free, and consumed it himself. 170 174 181

His new Azure Dragon power made him euphoric and convinced him that he could finally become Oak’s “big brother.” Oak defeated him shortly afterward with the newly acquired Paw-Paw Fruit, leaving visible lumps on Kaido’s head. 182 185

Kaido later joined Rocks, Oak, and Newgate in confronting the World Government’s ultimate forces. He supported Oak against Garp, fought Garling after protecting Oak from a sneak attack, and helped forcibly evacuate Rocks from the danger posed by Imu’s Black-Turn Domination. 161 162 165

When Imu returned through Garling’s body, Rocks used Kaido’s dragon form as a battlefield platform before ordering him to descend and escape. Rocks then formally disbanded the Rocks Pirates so that his remaining crew could survive. 209

Post-Rocks Era and Capture

After the Rocks Pirates’ dissolution, Kaido rejected Linlin’s demand that Oak join her and proposed that he and Oak form the strongest violent pirate crew in history. Oak refused all recruitment offers, leaving Kaido to establish his own path. 211 212

Kaido later rushed alone toward Hachinosu after learning that Ochoku had appeared there. The Marines anticipated his impulsiveness and captured him with Seastone in an ambush overseen by Garp, Sengoku, and Zephyr. 250

Thirty-six years after Oak’s supposed execution, Kaido reacted violently to the news, attacked a Navy fortress, and flew toward Marineford to investigate. In the ensuing decades, he rose as one of the Four Emperors. 264

Emperor Era

As captain of the Beasts Pirates and an Emperor, Kaido became a near-invulnerable ruler of Wano. He repeatedly fought Marine Eagle, acknowledging the younger fighter’s progress but refusing to kill him because of Eagle’s connection to one of Kaido’s old companions. 315 316

Kaido’s relationship with Yamato is deeply hostile. Yamato views Kaido as an oppressor, recalls Ace’s invasion of Onigashima, and actively hopes that challengers such as Eagle can defeat him. 315

Reunion with Oak

Kaido recognized Oak’s survival from his familiar behavior, handwriting, fighting style, and bear-paw-shaped crater. Overwhelmed by shock and excitement, he immediately departed Wano in Azure Dragon form to find him at Mock Town. 353

Their reunion at Thriller Bark begins with Kaido attempting to establish himself as Oak’s new “big brother.” He uses Bolo Breath, Thunder Bagua, Three Realms: Ragnaraku, Kundali Dragon Swarm, Drunken Thunder: Naraku, and Rising Dragon: Flame Bagua, but Oak remains overwhelmingly stronger. 361 362 364 365

Their Conqueror’s Haki collision splits the sky over the Florian Triangle. Although Kaido demonstrates tremendous growth in strength, physique, and Haki, Oak eventually beats him into submission and reasserts their original hierarchy. 363 364 366

Thriller Bark Aftermath

After accepting Oak’s authority again, Kaido brutally beats Gecko Moria for mocking him, then immediately becomes obedient when Oak arrives. He learns that Oak was trapped in the Rainbow Mist by Imu and becomes eager to attack Mariejois with him. 367

Kaido later complains to Oak about the powerful figures who mistreated him during Oak’s absence. Oak responds protectively, declaring that others have no right to bully Kaido and promising to settle accounts with those who continue to threaten him. 368

Return to the New World and Pirate Alliance

Reading of Oak’s victory over the Red-Hair Pirates and Rayleigh’s death, Kaido realizes that Oak had not fought seriously against him at Thriller Bark. Drunk and dejected, he beats Jack while blaming him for the Beasts Pirates’ standing relative to the other Emperor crews. He subsequently departs Onigashima in Azure Dragon form. 453

When Oak later summons him, Kaido leaves King and Queen in charge of Wano and flies to join him. He arrives during Oak’s sparring match with Newgate and Shiki and enthusiastically enters the fight, only to become a target for the two frustrated former Rocks Pirates and plead for Oak’s help. 465 472

Oak then proposes bringing his former comrades together in a pirate alliance against the World Government rather than restoring the old Rocks Pirates flag. Kaido is the first to commit, pledging the Beasts Pirates. He supports Oak’s plan to conquer the New World and welcomes the prospect of a war spanning the world. 474 475

Notable Quotes

“Although we're both apprentices, I joined before you. So, shorty, I'll be your big brother from now on.” 10

“Pirates have their code too. Never betraying your comrades is an ironclad rule.” 26

“Don't think it's like back then. I'm not afraid of you anymore!” 362

“Big Brother, that bastard mocked me first!” 367

“Big Brother, save me!” 472

“I'll be the first to join with the Beasts Pirates!” 475

Trivia

• Oak charges nearly 200 million Beli worth of tavern drinks to Kaido’s tab while Kaido is unconscious. 16 17
• Kaido initially considers stealing the Bat-Bat Fruit, Mythical Zoan: Vampire Form from Oak, then regrets hesitating after Oak eats it. 30
• Despite joining the Rocks Pirates before Oak, Kaido is persistently called “little brother” by Oak after losing their duel. 14 15
• Kaido stole the Azure Dragon Fruit from Linlin, though Linlin insists he owes her a lifelong debt for effectively “giving” him the fruit. 181 198
• His dragon form was large enough to serve as a platform for Rocks and several other fighters during the God Valley Incident. 209
• Kaido’s first instinct after learning Oak had returned from apparent death was to abandon Wano and fly directly to him. 353
• Although he insists that he no longer fears Oak, Kaido instinctively nearly admitted fault when Oak repeated the question used to discipline him during their youth. 362
• Kaido becomes stronger when drunk, a trait Oak compares to alcohol giving courage to a coward. 365