Dr. Indigo

Towering and theatrically clownish, Indigo has indigo hair with two oversized tufts at the sides and a white face marked by purple lines around the eyes that resemble makeup. His pot belly, thin limbs, and muscular chest give his torso the silhouette of a volumetric flask. Round purple eyeglasses rest on his forehead, and he wears a yellow polka-dotted indigo scarf, chest-baring indigo overalls with double rows of buttons, a lab coat, brown gloves, and indigo-striped shoes that emit a farting noise with every step. Two decades earlier he looked much the same, save for an orange lined scarf and no glasses on his brow.

Indigo is an eccentric doctor with a signature "Piro piro piro" laugh who delights in his flatulent shoes regardless of who they annoy. He frequently attempts to communicate through mime and charade-like gestures, only to break character by suddenly speaking, and he is genuinely startled whenever someone actually deciphers his pantomime. Cautious by nature, he keeps on hand at all times a vial holding the antidote for the Draft disease. With Shiki he forms a classic comedy duo, playing the straight man and slapping his captain whenever the latter does something foolish.

A skilled chemist, Indigo oversaw the development of Shiki's beast scheme and created the SIQ serum from Merveille's IQ plants. He fights capably enough to stand beside Shiki against the Roger Pirates and handles a large sword, and he is also an accomplished dancer in his captain's routines. His trademark technique, Chemical Juggling, produces glowing green and purple explosive orbs that he arranges overhead and fires one after another like a juggler; a condensed version called Mass Juggling builds a single far more destructive sphere that needs time to reach critical mass. Because he can pull himself out of water, he is clearly no Devil Fruit user, his powers instead stemming from chemicals applied to himself, which can backfire, as when he was consumed by his own flames after Zoro defeated him.

When the Golden Lion crew clashed with the Roger Pirates at the Edd War, Indigo stood at Shiki's side and stayed loyal through his captain's later imprisonment. Once the Golden Lion broke out and reached Merveille, he spent twenty years developing the serum to power Shiki's mutant army. In One Piece Film: Strong World, he performed dances for Nami, mimed key news to Shiki, and tried to attack Luffy with a sword before Zoro intervened. When Chopper and Usopp sought a cure for the infected Nami in the palace laboratory, Indigo refused to surrender it and battled Zoro, unleashing Chemical Juggling only to be swiftly beaten by Asura: Ugui as he lost control of his own power. The last anyone saw of him, he was plummeting senseless beside Shiki and Scarlet, his fate left unknown.