Dimentio

Dimentio is a malevolent, psychopathic jester who sought to use the Dark Prognisticus to end all worlds. However, he was stopped by Mario, Luigi, Princess Peach, and Bowser. Though it was assumed he was dead, it is revealed in Poncho's Adventures that he atcually survived. Following his defeat, he became aimless and drifted through the dimensions.

He is the reason Interdimensional Black Ops was created, and has spent a portion of the time since his defeat running from them.

He serves as a Chaotic-Neutral power in Poncho's Adventures, simply hanging around the Liver of Iron to stir up trouble or hide from Interdimensional Black Ops.

Trivia

 * Dimentio's name is a pun on the words "Dimension" and "Dimentia"