Dopefish

The Dopefish is a fictional fish that originated in the fourth Commander Keen video game, Secret of the Oracle, released in 1991. The character has since evolved into a PC game industry in-joke, making appearances in games from Apogee's 1994 Wacky Wheels as well as titles as recent as the 2006 SiN Episodes: Emergence and 2007 Chili Con Carnage and more recently including 2011's Deus Ex: Human Revolution and 2012 Natural Selection 2.