Caesar Clown

Caesar's body carries a perpetual smoky haze thanks to his fruit. He is rather tall, with long spiky black hair and a pair of curled horns rising from the back of his skull. Purple lipstick and dark shadow ring his features, which include a small flat nose, slender brows, and brown eyes the anime renders yellow; against his frame, his arms look oddly spindly.

His usual getup is a loose pale-blue coat lettered GAS in pink on both sides, worn over yellow-and-orange striped overalls cropped below the knee, with dark gloves stamped with his initials and bare feet beneath. Once he draws in the Shinokuni, his form blackens and balloons to giant scale, his hair runs wild, and a coral-shaped crown rises behind his horns, until defeat returns him to normal.

Caesar is a vicious, swaggering, and openly malevolent figure who savors the suffering he causes. The proofs of his cruelty pile up: a chemical blast that killed or maimed most of Punk Hazard, a trade in mass-killing weapons for clients like Doflamingo, and experiments on abducted children whom he hooks on a lethal, addictive drug so none can flee. By his own arithmetic those children would perish within five years, which he shrugs off as a worthy cost for science, all without a trace of regret.

Ego rules him utterly. Praise of his own work makes him flush with pride, while praise turned toward Vegapunk sends him into a rage. For all that bluster he is a coward at heart, begging Luffy, Doflamingo, and even the Straw Hats to spare him whenever his life hangs in the balance. He cackles a trademark Shurororo, is fond of a cocktail, and freezes into comic shock the moment something catches him off guard. Arrogant though he is, he can still recognize a job past his reach, as when he privately conceded that the gigantification work Big Mom demanded lay beyond his limits.

A gifted chemist, Caesar concentrates on biological and chemical arms dreaded even by the Marines' research wing. His handiwork includes the toxic gas that left Punk Hazard a dead wasteland and the towering slime beast Smiley, which he brought to life by feeding it an axolotl-model Sara Sara no Mi fruit. He alone can synthesize SAD, the ingredient required to mass-produce the artificial Zoan fruits called SMILE, a monopoly that made him priceless to Doflamingo and, in turn, to Kaidou's force of more than five hundred Zoan users. He even succeeded in enlarging ordinary humans into giants, something Vegapunk never managed, albeit through monstrous child experiments. For Capone Bege's strike on Big Mom he built the KX Launchers, poison weapons potent enough to threaten an Emperor.

His power flows from the Gasu Gasu no Mi, a Logia granting the ability to spawn, steer, and turn into assorted chemical gases, be they toxic, flammable, or able to drain oxygen and smother flames and foes. By absorbing outside gases he balloons in size and adopts their traits, picking up petrification from the Shinokuni. As gas he flies and seeps through sealed gaps yet can condense enough to grip objects, and he rounds out his arsenal with explosive Gastanets, a burner-like hilt for his Blue Sword, and a flintlock.

Caesar's villainy threads through several arcs. After laying Punk Hazard to waste he crept back to resume outlawed research until the Straw Hats and Trafalgar Law defeated him. Kept as a captive of their alliance, he later landed in Big Mom's grasp on Whole Cake Island, was sprung and pressed into Bege's plot to kill her, and finally fled with the Vinsmoke Family to Germa, where he and Vinsmoke Judge raised NEO MADS against the common foe they shared in Vegapunk.