Chill Penguin

Chill Penguin, known in Japan as Icy Penguigo (アイシー・ペンギーゴ Aishī Pengīgo), is one of the bosses from Mega Man X, a Reploid based on a king penguin designed for operating in sub-zero temperatures. He was a Maverick Hunter from the 13th Polar Unit that was deployed to guard a station at the South Pole, but soon grew tired of his dull, isolated life. When the news of Sigma's uprising reached him, he saw his chance to return to civilization. He destroyed his own commander, made his escape, and joined up with Sigma and other Mavericks.

He's rowdy and belligerent despite his small stature, and there is a strong animosity between him and Flame Mammoth due to Mammoth being a bully toward smaller Reploids and Penguin being jealous of his large size.