Gustaf Grefberg (born 1974) is a Swedish musician. As part of the Amiga scene, he is known under the artist name Lizardking, and much of his production is tracker music. He is or has been a member of the demo groups Alcatraz, The Silents, Razor 1911, The Black Lotus and Triton. He and Joakim Falk invented a musical style called Doskpop and he released various music disks such as "Doskpop The Compilation" or "Memorial Songs 1+2" which feature lots of tracks in this style. He also took part in projects such as Merregnon and the Symphonic Game Music Concert-series in Leipzig, Germany.

In 1994, he released a compact cassette, Mindlitter, in cooperation with Martin Wall. His songs are on side A and Martin's on side B. They were in person selling the tapes at the Assembly '94 demo party.