This pudgy weirdo is a boss from Super Mario RPG, and his fight in RMN World parallels the original in many ways. Not much is known about him because he hasn't been seen since his first appearance. What we do know is that he likes explosives, wants to become famous, and is more than a little bit crazy.

Incidentally, a Punchinello is a grotesque or absurd character, as they were called in Italian puppet shows.