Brian "Brylle" Rasmussen replaced initial drummer Per M. Jensen in Danish metallers Invocator. After Rasmussen recorded the 2002 demo with Invocator he left and was replaced by Jakob Gundel .
Since 2002 Brian Rasmussen has played in Mnemic. The band released their debut "Mechanical Spin Phenomena" in 2003 and a sophomore album in 2004 via Nuclear Blast Records.
In 2004 Brian "Brylle" Rasmussen started a new band with Signar Petersen (ex-Mercenary, strings) and vocalist Rene Pedersen: Transparant.
2006 saw Brian "Brylle" Rasmussen show up in Smaxone, the Danish melodic metal band also featuring Michael BÝgballe (vocals, ex-Mnemic), Casper Skafte (guitar; Elopa) and Claus Lillelund (vocals; Elopa).