Nagash or Lex Icon (born Stian Arnesen, May 7, 1978 [1]) is a Norwegian black metal musician. He plays guitar, bass, drums and keyboards.

He began writing music in 1992, together with Fafnir and Glaurung for a project called Troll. Fafnir and Glaurung soon left the band, but Nagash continued Troll as a solo project, playing guitar and keyboard. Wanting to be in a band and "express himself on all levels", he founded the band Covenant together with Blackheart in 1993. (However, after having released two albums, they had to change the name to The Kovenant due to a Swedish band already called Covenant.)

Gaining a good reputation in the black metal scene, Nagash was recruited as bass player for Dimmu Borgir in 1996. In 1999, he left Dimmu Borgir to concentrate on his career with The Kovenant. At the same time, he changed his stage name to Lex Icon in order to reflect the artistic direction The Kovenant had taken.

In 2004, now known as Lex Icon, he teamed up with Shagrath and formed a new stoner rock band called Chrome Division. In this band he played drums.

Lex has reported that he was fired from Chrome Division and is now 100% dedicated working on the next Kovenant album. He also now currently reported to have joined one of his favorite bands, Crowhead.

He has also been involved in Nocturnal Breed (as a session drummer, under the name of Rick Hellraiser) and Carpe Tenebrum.