Caesar Clown (シーザークラウン , Shīzā Kuraun) is an antagonist in the One Piece series that was created by Eiichiro Oda. The series first began serialization in Shueisha's Weekly Shōnen Jump on August 4, 1997. He would later appear in the Punk Hazard Island Arc that began in Volume 66.
His first appearance was in splash page on One Piece Volume 67 CH. 658 "Biscuits Room".
Caesar has a very gaseous look due to his Devil Fruit ability. He has very long, spiky, dark purple hair, brown eyes (yellowish in the anime), and two curly horns growing from the back of his head. He is rather tall (shown to be about the same height as Brook when standing next to him with his gas powers deactivated), and wears purple lipstick and dark makeup on his eyes. He has a small flat nose and long thin eyebrows. His arms are very thin in comparison with to rest of his body.
Caesar wears a big light blue colored coat with "GAS" printed in pink on each side (in his first appearances this was not present). Under his coat, he wears a pair of diagonally striped yellow overalls which are striped cross with orange lines. The overall is cut off right under his knees, exposing his hairy legs. He also wears dark purple gloves with the initials "CC" in white on them. Due to his constant gaseous form, he seems to not use shoes, remaining barefoot, though only when his powers were disabled, his feet solidified with the rest of his body along with a simple pair of shoes.
After absorbing the Shinokuni, Caesar's entire body structure changed to a darker gas color matching that of the gas, becoming as comparably large as a giant, with his hair growing completely wild and overly long. He also grows a coral-shaped crown behind his horns. The word in kanji "Land of Death" (死国?) is written on the front of his chest. Upon his defeat, he returns to normal.
When under the service of Capone Bege, he disguised himself by wearing a blue shirt with an aqua scarf and suspenders while donning a spiky hairstyle that covered his horns. While part of the Sanji Retrieval Team-Fire Tank Pirates Alliance, he wore a yellow suit.
Caesar is, in Smoker's words, "one very crazy bastard", and his actions on Punk Hazard validate the Marine vice-admiral's claim. A very cruel, arrogant, scheming, sinister, and overall very evil person, Caesar takes great delight in causing harm and destruction to anything and anybody around him. His psychopathic nature is displayed many times, such as when he set off a chemical weapon on Punk Hazard, killing or crippling most of its inhabitants and destroying its environment, selling or creating weapons of mass destruction for similarly unscrupulous individuals such as Doflamingo, performing sick experiments on children and drugging them with a lethal, addictive drug to ensure that they do not run away, and trying to murder everyone on Punk Hazard (Trafalgar Law, the Straw Hats, Smoker's Marines, the children, and his own blindly following minions) so he could test out his new poisonous gas weapon-pet, Smiley – all of which he does without a shred of remorse or empathy for his potential victims.
He also appears to be able to act or lie on several occasions, often being seen feigning emotions when lying to his subordinates and to the children, a trait that was quickly noted by Monet when he attempted to show false concern for his subordinates facing Smiley. However, with the blind trust of his subordinates and some crocodile tears, he was able to deceive them easily, leading them to believe that Vegapunk was responsible for the Punk Hazard explosion four years ago. Caesar also is very ill-tempered and quick to anger when things do not go his way, such as yelling at his subordinates to let the gas come in to kill the intruders and his own men and again when Monet pointed out that Vergo would die and Caesar just yelled, unconcerned about his potential disloyalty. Upon losing the upper hand against Luffy during their last fight, Caesar lost his composure and ordered his subordinates to let in the Shinokuni gas, while outwardly exclaiming that they can easily be replaced. He then goes as far as personally killing the ones present simply to test out his newly acquired power, revealing his true colors in the process.
He has shown to have maniacal tendencies due to his sedulous research on weapons of mass destruction and his absence of emotion at the time of murdering people or provoking any type of suffering such as giving drugs to the children so they would suffer severe withdrawal and return to his research facility for more "candies" filled with the stimulant, and showing no regret or sorrow for his actions.
He has a distinct laugh of "Shurororororo"
Gasu-Gasu no Mi
This Devil Fruit's main strength is the ability to change into a gas-like form, allowing the user to float and go inside places that normal beings cannot, as Caesar Clown was seen hiding inside some flasks when he was informed that the Marines were nearby. However, he can also become dense enough to hold objects, like his cocktail glass. As explained by Brownbeard, he claimed to be the one who purified the whole island from poisonous and nerve gases. This however is revealed to be just a cover story, with the poisonous gases being used to give birth to Smiley.
The gas that Caesar produces is very poisonous. The gas appears to be explosive when set alight, which allows Caesar to create controlled explosions without harming himself. Additionally, the user has the power to manipulate other preexisting gases in any given location, and can suffocate their opponents by removing the oxygen in the area. This gives the user two options to instantly defeat their opponent, allowing Caesar to knock out Luffy after realizing that Luffy was immune to poison (however the area effect is finite, so if someone escapes the oxygen-free zone they will be able to breathe again). They can even merge with such gases to enhance his own power, depending on the gas being absorbed, all the while being immune to the toxic effects himself.
The gas form appears to be weak against fire, although this is mitigated by the user's ability to minimize oxygen levels in the surrounding area, preventing combustion. On the other hand, it seems to take some concentration or is only possible while solid to manipulate the oxygen, as Usopp and Nami could breathe again when Brownbeard struck Caesar with a metal pipe, and there seems to be a range of which Caesar can control oxygen, leaving him more vulnerable to longer-ranged attacks. Also, many of Caesar's techniques require external ignition and tools to work.
In direct combat, Caesar has also proven to be a very powerful fighter, using his Devil Fruit abilities to quickly maneuver out of dangerous situations and being durable enough to take several Haki-imbued Gear Second strikes from Luffy, only to emerge relatively unharmed. His durability extends to being seemingly unfazed by either the boiling hot or the sub-zero temperatures which compose the "Burning Lands" and the "Ice Lands" zones on Punk Hazard respectively. He withstood a blow from Luffy that left a big dent in his face and still retained consciousness. He is also very stealthy, being able to administer a muscle relaxant to Brownbeard without the latter noticing. Caesar also has the power to combine with Shinokuni and become stronger. After this transformation, Caesar can petrify anyone he touches. Capone Bege acknowledged Caesar's potential and believed that his assistance would be vital in his plot to assassinate Big Mom. Caesar is also physically strong, able to easily carry around a large and tall mirror which the Straw Hats and the Fire Tank Pirates would use to escape. Caesar also assured his confidence in carrying Brûlée, who is a very tall woman while bringing along the mirror. Caesar has a strong will being able to withstand a burst of Big Mom's Haoshoku Haki.
Caesar is an outstanding scientist with immense scientific and chemical expertise, as he was Vegapunk's second-in-command and had a particularly high expertise in creating dangerous biological and chemical weapons that the Marine's Science Division including Vegapunk greatly feared. Caesar was able to cause a chemical weapon explosion from one of his experimental weapons that rendered Punk Hazard a barren wasteland. He was able to turn normal humans into giants, a feat that even Vegapunk could not accomplish, though Caesar has resorted to illegal and inhumane methods that Vegapunk considers unacceptable (by forcing vast amounts of dangerous drugs down their systems), and the fact that the children used would expire within five years from the continuous experiments, which led the Marines to refuse to acknowledge him to be superior to the head scientist. He also uses the highly restricted drug NHC10, though his authorization on its usage is illegal, as he is a criminal, and he used it as for its addictive means instead of medicinal purposes. He is also in the possession of another unnamed drug, that relaxes muscles and makes it unable for the person, who the drug has been injected into, to talk or stand. All this earned him recognition as the world's leading expert on mass murdering weapons for biological warfare. His expertise in creating and designing weapons for biological warfare is so great that Capone Bege recruited him in his plot to assassinate Big Mom. Caesar was able to create the KX Launcher, a weapon with poison strong enough that could potentially kill a Yonko, and managed to prepare three for the Fire Tank Pirates to use within a fairly short period of time.
Derived from his scientific expertise, he invented massively destructive weapons, the most prominent one being a pet slime named Smiley, a mountain-sized lump monster that constantly emits some kind of smoke or vapor and has been "fed" the Sara Sara no Mi, Model: Axolotl (which gave the once inanimate lump life and form), which Caesar would unleash when trespassers become too much of a threat. He can control Smiley by using verbal commands, demonstrated when he ordered the Smilies to attach themselves to Luffy, and they obeyed.
Caesar is also the only person who knows how to produce a substance called SAD, a rare and valuable substance that is an essential ingredient for the creation of Artificial Zoan Devil Fruits called SMILE, another feat that Vegapunk has failed in. Because of this, Doflamingo values Caesar's work greatly, as he apparently employs the scientist's expertise to cater the military expansion demands of one of the Yonko.
He was seen using a dual-barreled flintlock to threaten Law when he learned of his past associations with Luffy. He was also shown using various weapons in conjunction with his Devil Fruit abilities; like explosive red and blue castanets filled with volatile gas called "Gastanets" which he claps together to create a massive explosion, using matches to ignite a gas he calls "Miok Gas" to cause an explosion in the immediate area, and a sword hilt, bearing some similarity to a Bunsen burner, that he concentrates oxygen in to use a technique called "Blue Sword". He also used a syringe to inject a muscle relaxant into Brownbeard stealthily to prevent his subordinates' trust from being compromised.
Major Story Arcs
Punk Hazard Island Arc