I find Morbid Angel and Death waaaaaaaay overrated, so it is a matter of opinion to the extreme. Atmosphere will always beat out riffs and technicality.
Ok... please explain. Altars of Madness and the old Mantas demos along with Into the Pandemonium and Scum are responsible for creating extreme metal. If all you had heard was possessed and kreator, Altars of Madness was a fucking revelation. No atmosphere? Wow... just... don't even know what to say. Does anyone who remembers grabbing SBG or Altars back in the late 80's actually feel this way too?
D.