Bloodbath

I probably wouldn't call them straight-up old school death metal, though some songs are most definitely like that, a lot of the songs are quite techincal for old school DM. Either way, a very good band and yes it's pretty brutal.

the stuff on breeding death is, pretty much old school DM but the newer one has a tinge of BM
 
its all old school death metal, if you liked left hand path by entombed, you'll love breeding death, and if you love breeding death, you'll love the rest, peter tagtgren does vocals on nightmares made flesh, its wicked, also blackheim and jonas renske from katatonia are in it too, so is axe