Karl Deckard started his career as a graphic design artist at Nintendo Power magazine. He also worked on several official player's guides for games like Yoshi's Island and Killer Instinct. His first development job was at Valve, where he worked as an artist and designer on the seminal Half-Life. He left Valve to join Blizzard Entertainment in 2000 and was credited in Diablo II. He left Blizzard to join Retro Studios and worked on the Metroid: Prime Trilogy. He is currently working on inFAMOUS 2 at Sucker Punch.
He is an avid skateboarder and plays a lot of Tony Hawk games. [Source]