Muchana

Muchaner is a doctor who works at Impel Down's medical room.

Impel Down Arc
In the medical room of Impel Down, Bentham (disguised as Hannyabal) ask him about Luffy's condition after Magellan's attack. He tells him it is impossible to create an antidote to counteract multiple poisons from Magellan at once, and there is no way to save him..