Caesar Clown of One Piece

Caesar clown is a former colleague of Vegapunk and a leading expert on weapons of mass destruction. He has ties to the underworld as well as the Four Emperors. On the island of Punk Hazard, he conducted secret, forbidden experiments on children, trying to turn them into giants. Caesar conducted this research on behalf of Big Mom, from whom he swindled immense amounts of research money.

He was also responsible for the production of SAD, a key ingredient in artificial devil fruit, which Donquixote Doflamingo sold to Kaidou. This trade was disrupted by the intervention of Luffy and Trafalgar Law’s Pirate Alliance. He then served as a pawn of various interests, traveling to Zou with the Straw Hat Pirates before being turned over to Big Mom by Capone Bege. After the failed assassination attempt, he regained his heart and presumably escaped.


Caesar Clown inits gas form.

Caesar is a big man. A wild black mane adorns Crown’s head, from which two horns protrude. He has a long, narrow nose and a comparatively large mouth. He wears a yellow, striped, full body suit as well as dark gloves. Over this, he has a wide light blue coat with GAS written on the front, in large pink letters. As a user of the Logia-type gas fruit, he can also transform into gas.

When he bonded with Shinokuni, his appearance changed tremendously. For example, he grew to the size of a giant and his hair became much longer and wilder. Furthermore, his horns also grew and took on the shape of a crown.

Four years ago his hair was shorter and not as wild as it is now. Also, he was still wearing a polka-dotted jumpsuit back then.


Caesar Clown is a very hypocritical, ruthless and sadistic person. In his selfish nature, Caesar acts without pity or compassion. He conducted drug experiments on children who would have died from them without help. He was also willing to kill everyone present on Punk Hazard, including children and his own subordinates. Due to his great intellect, Caesar sees himself as Vegapunk’s rival and therefore also tries to prove that he is the best scientist in the world. He does not see mistakes on his part because of this, including saying that the explosion and spread of his nerve gas four years earlier on Punk Hazard was not a failure. He was also visibly proud of his own work on Zou regarding his massacre gas Koro or when his work is praised. He became angry, on the other hand, when Luffy compared his ability to produce poison gas to Magellan’s devil powers.

According to Caesar, no one should trust anyone else, so he was amused by Law or Luffy, among others, because of their alliance. But he also made fun of Brownbeard when he tried to expose Caesar’s true intentions. He gave him a muscle relaxant so he couldn’t speak properly. Caesar’s men laughed at him because of this. To achieve his goals, he did not shy away from bold-faced lies. He played up to his subjects as a great benefactor, even though he saw them as nothing more than guinea pigs for his latest weapons of mass destruction. He also deceived the children to gain their trust and to get them to join him. He even lied to Big Mom, seeing himself protected in the guise of Doflamingo and Kaidou.

In addition to his mischievous nature, Caesar is very concerned with his safety and acts cowardly when he sees his life in danger. When Caesar realized that Luffy would not be stopped by his threats by Doflamingo and Kaidou, he desperately offered the latter to join his organization so that Luffy would stop his final attack. Also, when Big Mom’s pirate gang showed up, he begged the Straw Hats not to turn him in because he had swindled research funds from her. He was also manipulative when the Straw Hats reminded him several times that they were in control of his heart. Among other things, he reluctantly helped them enter Zou or neutralize the poison gas Koro with his powers.

Skills and Strengths

Caesar is a scientist who has experimented side by side with Dr. Vegapunk on Punk Hazard. He’s also the foremost expert when it comes to weapons of mass destruction. This suggests that he is a highly intelligent man.
Additionally, he has eaten of the Logia type gas fruit, giving him the ability to turn into gas and produce some. With its help, he was also able to escape from a prison ship. Because of this, the World Government had a bounty of 300 million berries placed on his head. After the gas accident on Punk Hazard, it was also Caesar who filtered the gas out of the air. However, he is also able to remove oxygen from a certain radius around him due to his Devil Fruit, which enabled him to defeat Robin, Franky, Tashigi, and Smoker without touching them.

He also showed interest in Chopper’s Rumble Balls, claiming to be able to increase the Monster Point’s effect to 30 minutes with some chemicals. Chopper seems to have taken to this and it worked, as Chopper was already able to stay in Monster Point for much longer on Onigashima.


Working with Vegapunk

Caesar when he was still a member of the science team.

At one time, Caesar worked together with Vegapunk and Vinsmoke Judge. Then four years ago Caesar worked with Vegapunk again and they did research on Punk Hazard. What the goal of their work was is unknown. Caesar was working on a poison gas weapon at the time, which his colleagues thought was too dangerous, as it could have put civilians in danger. However, Caesar did not care. He claimed that these were necessary sacrifices and that only, then Admiral, Sakazuki would understand him. He mocked Vegapunk’s failed attempts at giant research, saying that all it would take was kidnapping a few children as test subjects. However, shortly after, Caesar was dismissed from the science team by Vegapunk because he could no longer cover up Vegapunk’s horrific experiments and could no longer tolerate Caesar’s behavior. Enraged by this, Caesar then unleashed his poison gas on the island.

Secret research

Caesar squanders Big Mom’s research money

After an incident attributed to Vegapunk rendered the island uninhabitable, Caesar was forced to leave. He also had a bounty of 300,000,000 berries placed on his head after his escape from the prison ship. He later returned and began conducting experiments on kidnapped children in secret. He freed the island’s prisoners and made them his subordinates, blaming Vegapunk for the poison gas accident. Using his powers, Caesar filtered the poison gas from the atmosphere, but collected it in secret to create his creature Smiley.

One day, he entered into negotiations with Big Mom, who had heard of his gigantification research and had taken an interest, wishing her family members to be the same size as her. To that end, he had children kidnapped, believing they had a disease he was trying to cure. In fact, he used the children for his experiments to make giants out of them and gave them the drug NHC10 in the form of candy, knowing full well that the children would die from it after a few years. Although his research was unsuccessful, Caesar continued to collect funds from the Empress, and since Caesar was the only one who could produce the SAD, Donquixote Doflamingo allied with him so that he could use the SAD to make artificial devil fruit (Smile). In return, the Samurai of the Seas used his connections to cover up Caesar’s activities. However, the Samurai of the Seas infiltrated Mone as Caesar’s assistant to keep an eye on him.

Meeting with Law

Caesar meets with Law.

A year after the battle on Marine Ford, Trafalgar Law showed up on Punk Hazard. The latter wanted to stay on the island for a while. In return, he helped Caesar’s subordinates get new abdomens, as they were paraplegic from the poison gas. But to really make sure that no one cheated the other, Caesar demanded Law’s heart, in exchange he would receive Mones.


The prisoner escape

Caesar, in his gas form, investigates the cell.

After the Straw Hat Pirates landed on Punk Hazard, they split into two groups. The group that remained on the Thousand Sunny was gassed by Caesar’s men and imprisoned in the research building, from where, however, they were able to break out. Caesar had then examined the prison and realized that the weapon used to blow the door must have been a Vegapunk laser. Suddenly, another of his subordinates appeared and reported that a Navy battleship had appeared. Caesar ordered it to be eliminated somehow, even if it was by a large amount of poison gas. As it turned out, however, the marines were persistent and were getting closer and closer to the research facility. Caesar was far from pleased by the news that the commanding officer was Smoker. He gave orders for everyone to hide. He himself found shelter in an experimental glass structure.

The navy shows up

Caesar getsSmoker’s heart from Law.

A short time later, however, Caesar had made his way back out of the container. His subordinates had reported to him that the escaped pirates had taken the children of the Biscuits Room with them and had run into Smoker and Law at the main entrance. That the Navy now knew about the children was a thorn in Caesar’s side. He also knew he couldn’t kill the marines or they would become aware of his activities on Punk Hazard. Shortly after, the harpy Mone appeared and reported that both Vegapunk’s dragon and Brownbeard’s centaur force had been defeated. This meant that there were other pirates on the island besides the escaped prisoners. The harpy explained to Caesar that it could only be the Straw Hat Pirates.

Later, one of Brownbeard’s men came to Caesar to inform him that Brownbeard had been kidnapped by the Straw Hats. Caesar pretended to help the injured centaur and promised to take care of Brownbeard as well. In fact, he was just using the guard as a guinea pig for his latest poison gas. Caesar then sat down with the recently returned Law. The latter delivered Smoker’s heart to him. Caesar then sent some guards to take care of the Marine. To get the children back and to get rid of the Straw Hats and Brownbeard, who turned out to be useless to Caesar, he sent out the Yeti Cool Brothers Rock and Scotch. When Caesar learned from Mone that Law had helped Luffy, he suspected Law of bringing Luffy to the island, which Law denied.

Caesar intervenes personally

Caesar defeated them all.

To dispose of the Marine as well as the Straw Hats, who had survived the Yeti Brothers’ attack, Caesar released his beloved creature Smiley. As the creature attacked the G5 unit as well as Luffy, Robin, and Franky outside the lab, Caesar appeared to revel in the suffering of his opponents. However, while he was still beaming around, Luffy took the opportunity to try and capture him. However, thanks to his abilities, Caesar was able to escape. A fight ensued between the two, which initially went in Luffy’s favor. Just when it looked like Luffy had won, he collapsed and went down as Caesar removed the oxygen around him. In this way, he was able to effectively defeat Robin, Franky Tashigi, and Smoker as well and carry them off.

After the enemies were locked up in the lab, Caesar set off in an airship to get the children. Nami and Usopp tried to stop him, but had no chance against him. Brownbeard too now stood up to his former master after realizing what kind of man he was. He demanded his men from the latter, but Caesar explained that these were now his subordinates and Brownbeard was nothing but trash in the New World. After the children left the cave, Caesar blew it up, hoping to get rid of the last of the troublemakers.

Test run of Shinokuni

Caesar wants to show off Shinokuni.

After this was also done, he turned his attention to his prisoners in his laboratory to taunt them. Then he finally wanted to present his newest weapon: Shinokuni. To do this, he had a video link set up with several different pirate gangs as well as obscure underworld organizations so they could view the weapon and suggest prices. Out in the winter tundra, he had a massive candy set up that was meant for Smiley. The candy contained substances which Smiley was to turn into his new deadly poison gas. Contrary to Caesar’s attempts to talk to him first, Smiley simply swallowed the candy. This turned Smiley into Shinokuni, a gas that immediately turned some of Caesar’s men who were still outside into stone statues. Pleased with his success, Caesar immediately wanted to give another demonstration and brought the cage containing Luffy and the other prisoners outside.

Fights in the lab

Brownbeard tries to warn everyone about Caesar.

But his prisoners managed to escape and let the Navy and the rest of the Straw Hats into the lab. When Caesar heard this, he planned to fill the entire lab with Shinokuni. After Vergo went off to take care of the intruders, Luffy and Smoker showed up at Caesar’s place some time later. Smoker, however, gave chase to Vergo and left Caesar, leading to another fight between him and Luffy. Now that Luffy was more aware of the latter’s abilities, he was better able to fight back and was once again on the verge of defeating Caesar. But this time Mone interfered. She wanted to give Caesar time to get to safety, whereupon he sought shelter in the Secret Room. During his escape he heard that Law was seen in the SAD production room, whereupon his motives became clear to him. Further, he received orders from Doflamingo to return to Dress Rosa with Vergo and Mone after the Straw Hats affair.

Luffy’s final battle against Caesar.

In the Secret Room, he explained to his men his tactic of driving all their enemies into Room R by filling the other rooms with the dangerous gas. Once they had all arrived in Room R, he would have it locked and then deliver them there to the gas. Brownbeard was the first to arrive in Room R and demanded that Caesar release his men.

Caesar came out of hiding with his subordinates and pretended not to know what Brownbeard was talking about. When the latter wanted to tell the others what Caesar’s true intentions were, Caesar secretly injected Brownbeard with a sedative so that he could not speak properly. Caesar secretly whispered to him that he was responsible for the disaster four years earlier, whereupon Brownbeard attacked him. Caesar told the guards that Brownbeard had gone mad and ordered them to shoot him. As Caesar was about to give him the coup de grace, he was stopped by Luffy.

This he explained how important he was to Doflamingo and one of the Four Emperors, and that Luffy would thus also mess with them if he attacked him. However, this did not matter to Luffy. Caesar even blabbed during the fight, making all his men in the surveillance room realize his true character. In order to keep up with Luffy, Caesar joined forces with Shinokuni and grew significantly, but he was still no match for Luffy. With a gum-gum grizzly magnum, Luffy hurled him out of the lab, where he was catapulted against his tanker.


Caesar stabs at the heart.

Lying on the tanker, Caesar regained consciousness some time later. Seeking revenge, he tried to kill Smoker and took out the heart Law gave him. He staked the heart, causing its owner to die, not knowing that Law had actually handed him Mones heart, which is why she died. Baby 5 and Buffalo, upset by the fight with Franky, found Caesar and tried to escape with him to Dress Rosa. But the escape was thwarted by Usopp and Nami. When Caesar tried to escape alone, Usopp blasted him with sea stone handcuffs, causing him to fall into the sea. A little later, they fished him out and put him in chains. When the G5 soldiers saw that Kinemon survived the rigidity he received from Shinokuni, they forced Caesar to tell them how to save their companions who were exposed to the poison gas. Later, Caesar was taken to the Thousand Sunny so that Law could use him as leverage to blackmail Donquixote Doflamingo into giving up his title as Samurai of the Seas.

Dress Pink & Green Bit

Caesar sits with the delivery team in the cafe before the bridge to Green Bit.

Once on Dress Rosa, Law, Robin and Usopp were to take Caesar to Green Bit, where Doflamingo was to pick him up. Outside a café, they looked together at the iron bridge leading from Dress Rosa to Green Bit, with a waiter telling them that the adjacent island was infected with Fighting Fish, which shocked Caesar so much that he wanted to change the location of the exchange, with Usopp assisting him. The scientist also became even more panicked when he overheard that three members of the masked CP 0 were present, which – according to Robin and Law – always spells trouble.

As the delivery party crossed the Iron Bridge, they were immediately confronted by the Fighting Fishes, who Usopp and Robin had to fight because Law wanted to conserve his strength. In order to help the archaeologist and the gunner, the Samurai of the Seas had Caesar released from his sea stone handcuffs and removed his heart so he could help against the sea creatures, which visibly angered the scientist and whereupon he vowed revenge on the captain of the Heart pirate gang. After reaching the Small Island, the team discovered that a Navy ship had capsized on Green Bit’s southern beach, at which point Caesar loudly demanded that the exchange be called off and became very concerned about being apprehended by the Navy.

The Straw Hats use Caesar for their counterattack.

Shortly thereafter, Admiral Fujitora appeared with his naval unit as well as Donquixote Doflamingo. Due to Doflamingo’s scheming about not having given up his samurai title, Law was forced to call off the exchange with Caesar. He fought Fujitora and Doflamingo, and made sure Caesar was handed over to the Sunny squad that had sailed to Green Bit. After Sanji joined the squad, they decided to escape the danger from Doflamingo and head for the next island, Zou.

The Sunny escaped Doflamingo through Law’s sacrifice and moved further and further away from Dress Rosa. However, during a briefing with the members on Dress Rosa, Big Mom’s pirate ship suddenly appeared with Pekoms and Tamago. They located Caesar on the Sunny, whom they were trying to take into their custody. Caesar was shocked to see Big Mom’s gang, as he had swindled research funds from her, and begged the Straw Hats not to turn him over to them. The Sunny squad had every trouble escaping the enemy pirate ship as they were attacked. Caesar had to reluctantly work with the Straw Hat Pirates to fend off the cannonballs. Eventually, the Sunny escaped with a coup de bust. Unfortunately, Pekoms and Tamago had overheard the Straw Hat Pirates heading for Zou and sailed after them.

Hostage situation on Zou

Sanji takes Caesar hostage.

The next day, the Thousand Sunny reached Zou. With the help of Caesar’s gas balloon, they flew up on the elephant. The island had been attacked shortly before by Jack, who had released one of Caesar’s poison gases to kill the Minks. The poison gas cloud was still hovering in the air when the Straw Hats entered the Duchy of Mokomo. Visibly proud of his invention, Caesar celebrated himself for this unexpected success of his weapon of mass destruction. Chopper, on the other hand, lambasted the scientist for his statements. Sanji reminded him that they were still in possession of his heart and forced him to neutralize the remaining poison gas on the island so they could treat the injured Minks. He then helped Chopper make medicine for the Minks.

Eight days later, the Big Mom pirate gang reached Zou. Caesar panicked and begged Sanji not to hand him over to Pekom and Capone’s Bege. Capone managed to capture the Straw Hats and Caesar using his devil power in his body. The pirate captain delivered Sanji an invitation to Big Mom’s tea party, where Sanji was to attend as the groom. The Cook decided to accept the invitation for the time being to settle the matter. He hurled Nami, Chopper, and Brook out of Capone’s fortress and took Caesar hostage to guarantee his safety and that of his friends. After Nekomamushi showed up, Capone made his escape. He took Sanji and Caesar to Big Mom’s ship, which sailed to Whole Cake Island.

Old Bills

Big Mom reminds Caesar of their mutual agreement

On the way, Caesar was locked in a cage and Sanji decided to give the scientist’s heart to Vito. He was later brought to Big Mom herself, who asked him about the progress of his Gigantification research, which she had supported with generous payments over the years. In doing so, Caesar attempted to place the blame on Luffy and Law, who had destroyed his lab on Punk Hazard, and with it his previous research. To his shock, Big Mom revealed to him that her eldest son, Perospero, had already built an explicit duplicate of his lab on Whole Cake Island using his devil powers. The latter also threatened him that if his research did not deliver the desired and promised success within two weeks, he would turn him into a living candy man and lick him to death. As a result, Capone was given Caesar’s heart and he was also put in charge of surveillance of Caesar, who wanted to get the scientist on his side to get rid of Big Mom once and for all.

The alliance to kill a Yonko

Capone, Caesar and Luffy form an alliance

The night before the wedding, Jinbe initiated a meeting between Capone and Luffy, who wanted to form an alliance to take down Big Mom. Caesar disguised himself more poorly for this purpose, posing as ‘Gangster Gastino’ (jap. ギャングスターガスティーノ, Gyangusutā Gasutīno), though most of those present quickly saw through his disguise. Those present lost themselves in minor squabbles, which were however arbitrated again by Jinbe, who reminded those present that they all had a common goal in the form of Big Mom, bringing them to their senses. Caesar’s part in the plan was primarily to create the so-called KX rocket launchers, which would be equipped with a deadly gas that, if used properly, would instantly kill Big Mom. Likewise, the scientist was to facilitate the escape plan, and in exchange for his services, finally regain his heart, and thus his freedom, after numerous weeks.

The tea party from hell

Just before the wedding, after having cut off all means of escape for the Big Mom pirate gang, Caesar positioned himself outside the wedding grounds with the escape mirror, which they planned to use with the help of the captured Charlotte Brûlée and her devil powers to quickly get back on their ships.

The escape plan fails

While the commotion broke out, destroying the wedding cake and the sacred image of Carmel, Caesar ran through the mirror world with Brûlée to further prepare the escape plan. He was surprised, however, that Big Mom still hadn’t started screaming, allowing the KX missile launchers to be used. Finally, Capone, Vito and Gotti did fire the deadly weapons at the paralyzed Big Mom, however, they were destroyed by her bloodcurdling scream. Panicked, Capone ordered a retreat, which is why Caesar flew towards them with the mirror. Just before they could all flee to its safe interior, it too shattered into a thousand pieces by Big Mom’s scream. This left Capone with no choice but to turn himself into a massive fortress, while the Big Mom pirate gang surrounded those present to take revenge for the strife they had caused. Capone, who was badly wounded by Big Mom’s attacks, then suggested that he change back to normal size before Caesar flew him to the coast. The latter vehemently disagreed, as he could not stand up to the combined fighting power of Big Mom and her children. Only after the Germa 66, Luffy and Sanji launched a diversionary maneuver did the scientist agree. On their way away from the plateau, however, numerous children, including Katakuri and Brûlée, stood in their way, but some of them were held at bay by the Vinsmokes and the Straw Hats. For a brief moment, however, it seemed as if the alliance had been overwhelmed by the combined fighting power of their enemies when the Tamatebako unexpectedly exploded, bringing down the castle. Arriving safely on the shore, the Alliance split up and Capone returned his heart to Caesar, who disappeared, overjoyed and vowing revenge.


  • Caesar’s mark is “CC”, which is written on the telescreens of his subordinates, among other things.
  • He, like many other villains in One Piece, has a very distinctive laugh. In his case, it’s a “Shurorororo.”
  • His name Caesar clown (jap. シーザークラウン, Shīzā Kuraun) can also be romanized as Caesar clown. However, which spelling Eiichiro Oda intended is unknown, as in the original Japanese volumes, use of both variants was made in Latin letters (in the manga, chapter 663, itself is “Clown”, in the introduction boxes in the volumes it is Crown).
  • “Caesar Clown’s” naming and, accordingly, his physiognomic appearance is apparently an obvious reference to Cesar Romero, who played the Joker (character) in the Classic Batman TV series from the 60s.
  • Caesar Clown’s favorite foods are glucose and gazpacho.
  • He was apparently modeled after a Pierrot.

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