Bloodbath are a supergroup who comprise of members from Opeth and Katatonia.
They play pretty brutal death metal, they have 3 studio albums out and for me are a pretty awesome collaboration band. Mikael Akerfeldt made appearances for Bloodbath also.
Band Members
Anders "Blakkheim" Nyström – lead guitars, backing vocals (since 1998)
Per "Sodomizer" Eriksson – guitars (since 2008)
Jonas Renkse – bass (since 1998)
Martin "Axe" Axenrot – drums, percussion (since 2004)
Former Band Members
Mikael Åkerfeldt – lead vocals (1998–2004, 2005, 2007–2012)
Dan Swanö – drums, percussion (1998– 2004), guitars (2004–2006)
Peter Tägtgren – lead vocals (2004–2005)
Studio albums
Resurrection Through Carnage (2002)
Nightmares Made Flesh (2004)
The Fathomless Mastery (2008)
EPs
Breeding Death (2000)
Unblessing the Purity (2008)
Live
The Wacken Carnage (2008, CD/DVD)
Bloodbath Over Bloodstock (2011, DVD)[
Here are some songs I really enjoy from this group.
Mock The Cross
Death Delirium
Process of Disillumination
Ways To The Grave