Silenoz has been Dimmu Borgir's guitarist since they started. He also composes and writes lyrics for most of the band's songs.

He contributes backing vocals (on "Stormblåst", its re-record, and "Godless Savage Garden") and bass (on "Stormblåst MMV"). He also sung lead vocals on their debut album "For All Tid". At first, he was known only as Erkekjetter Silenoz (Arch-Heretic Silenoz in Norwegian).