Oskar Forss was a co-founder and during the years of 1987–1992 drummer

Drummer

A drummer is a musician who is capable of playing drums, which includes but is not limited to a drum kit and accessory based hardware which includes an assortment of pedals and standing support mechanisms, marching percussion and/or any musical instrument that is struck within the context of a...

 of Swedish

Sweden

Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....

 then-death metal

Death metal

Death metal is an extreme subgenre of heavy metal. It typically employs heavily distorted guitars, tremolo picking, deep growling vocals, blast beat drumming, minor keys or atonality, and complex song structures with multiple tempo changes....

 band Therion

Therion (band)

Therion is a Swedish symphonic metal band founded by Christofer Johnsson in 1987. The word "therion" comes from the Greek therion , meaning "Beast," i.e., that of the Christian Book of Revelation...

.

Music career

Oskar Forss was a drummer of a pre-Therion band called Blitzkrieg. Due to personal problems with Forss, band decided to split up in ca. March 1988 but soon reformed having line-up without Oskar. Forss back to band in the same year and music group changed its name to Megatherion, and shortly after to Therion. He recorded with the band all three demos and two first albums—Of Darkness...

Of Darkness...

Of Darkness... is a debut studio album released on February 1991 by the Swedish band Therion and it contains songs written in the early years of the band, during the 1980s. The album is indicated by the band itself as an end of its first era....

and Beyond Sanctorum

Beyond Sanctorum

Beyond Sanctorum is the second studio album released on January 1992 by Swedish band Therion. The album was re-released on November 27, 2000 under Nuclear Blast label as a part of The Early Chapters of Revelation box-set...

. After that recording, Forss was expecting his second child and decided to leave the band.

Discography

• Therion
  Therion (band)
  Therion is a Swedish symphonic metal band founded by Christofer Johnsson in 1987. The word "therion" comes from the Greek therion , meaning "Beast," i.e., that of the Christian Book of Revelation...
  
   – Paroxysmal Holocaust (1989)
• Therion – Beyond the Darkest Veils of Inner Wickedness (1989)
• Therion – Time Shall Tell (1990)
• Therion – Of Darkness...
  Of Darkness...
  Of Darkness... is a debut studio album released on February 1991 by the Swedish band Therion and it contains songs written in the early years of the band, during the 1980s. The album is indicated by the band itself as an end of its first era....
  
  (1991)
• Therion – Beyond Sanctorum
  Beyond Sanctorum
  Beyond Sanctorum is the second studio album released on January 1992 by Swedish band Therion. The album was re-released on November 27, 2000 under Nuclear Blast label as a part of The Early Chapters of Revelation box-set...
  
  (1992)