He is best known as the founder and guitarist of Bergen-based band Hades Almighty, and a former member of Immortal, Dominanz, Old Funeral and Amputation.

Tunsberg started his musical career in the late 1980s as a member of metal bands Old Funeral and Amputation.

Tunsberg was convicted for the arson of the Old Åsane Church on Christmas Eve 1992 along with Varg Vikernes and spent two years in prison.

"[3] In an interview with Sam Dunn for Metal: A Headbanger's Journey, Tunsberg stated that: "The most important thing that happened was that the church were burnt up.

He formed the solo project Vathr in 2022 and released the EP Dead & United later that year.