Stian Aarstad is a Norwegian pianist and keyboard player. He is a former member of the black metal band Dimmu Borgir in which he played keyboards and synthesizers. He is now the pianist for a band called Enthral. Stian Aarstad stole the melody "Sorgens Kammer", the 4th song (instrumental)on the Stormblåst album, from an Amiga game called "Agony".
He was said to have been fired from Dimmu Borgir for being drunk when rarely coming to rehearsals after taking a leave to enroll in the Norwegian army.
Stian Aarstad was well known for wearing his infamous top hat and cape on stage with Dimmu Borgir (an outfit reminiscent of Jack the Ripper) and minimal corpsepaint, and received much criticism about wearing such a babyish costume in a black metal band. When fans were asked what they meant by "babyish" they proclaimed their love for Satan and attacked the reporter with a metal studded cod piece.

During Enthral's third album Stian Aarstad left the band. He is sometimes a session player and engineer for the band. It is reported that he is now working as a sound engineer.

Back in the Dimmu days, Stian did not listen to ANY metal music at all; he preferred classical music.

(Source: Nationmaster.com)