Sverre André Kvernmo (alias Cranium) is a Norwegian level designer who started his career by creating Doom levels. He is one of the authors that contributed to the Master Levels for Doom II. In 1998, Doomworld nominated him one of the Top Ten Doom Level Makers‎ and conducted an interview with him. Outside of Doom, he has worked for Ion Storm, Xatrix Entertainment, and others, notably on Redneck Rampage, KISS: Psycho Circus, and Age of Conan.