He has created soundtracks for several games, including Enclave, The Chronicles of Riddick: Escape from Butcher Bay, Knights Of The Temple and The Darkness.
In the demo-scene, where he is better known as Lizardking, he often made innovative synth-dance music, which became known as Doskpop. He has been a member of demogroups Alcatraz, The Silents, Razor 1911, The Black Lotus and Triton.
Triton started working on an RPG game Into The Shadows, around 1994. Only one demo was released in 1995, which featured some game characters, showing off some fancy character animation. The project got canceled not long after this.
In 1998, a few members of Triton (like Magnus Högdahl) founded Starbreeze Studios AB, for which Gustaf Grefberg is still working today and where has won acclaim for soundtracks that he has made over the years. The soundtrack for The Chronicles of RIddick: Escape from Butcher Bay, for example, was awarded best game soundtrack 2004 by the leading German PC-magazine "Gamestar".
He has participated in Symphonic Game Music Concerts as well as in Merregnon, a soundtrack CD which features new music, written by video game music composers.