Jørn Stubberud (born 13 April 1968) is a Norwegian musician best known as the bassist in the black metal band Mayhem under the stage name Necrobutcher. He is one of Mayhem's founding members, along with Euronymous, Manheim and Messiah. He is the band's only remaining original member, as Messiah and Manheim left Mayhem, respectively, in 1986 and 1988, and Euronymous was murdered in 1993. He has also played in other bands, including L.E.G.O., Kvikksølvguttene, Bloodthorn (guest artist), and Checker Patrol.
Necrobutcher was in the band since 1984, but left in 1991 due to personal concerns following the suicide of former vocalist Dead as well as internal conflicts and disagreement with bandmate Euronymous. He was replaced as a session bassist by Varg Vikernes, who murdered Euronymous in 1993. In 1995, Necrobutcher reformed the band, along with Hellhammer, Maniac and Blasphemer. In 2018, he published the book The Death Archives: Mayhem 1984–94. He still plays in Mayhem.
In 2018, he released his retrospective book about the early stages of the band, The Death Archives: Mayhem 1984-94, published by Thurston Moore's publishing house Ecstatic Peace Library.
- De Mysteriis Dom Sathanas (1994)
- Grand Declaration of War (2000)
- Chimera (2004)
- Ordo ad Chao (2007)
- Esoteric Warfare (2014)
- Daemon (2019)
- Deathcrush (1987)
- Wolf's Lair Abyss (1997)
- Live in Leipzig (1993)
- The Dawn of the Black Hearts (1995)
- Mediolanum Capta Est (1999)
- Live in Marseille (2001)
- Live in Zeitz (2016)
- De Mysteriis Dom Sathanas Alive (2016)
- Live in Jessheim (2017)
- Live in Sarpsborg (2017)