Our difference of opinion shows because Cobalt isn't quite what I'm looking for. Good but not quite. I think of Lord Mantis as definitely blackened sludge, and it's more the black metal influences of ferocity I'm interested in. Stalking it's prey then fucking annihilating it, the atmospheric side. A band that doesn't necessarily have balls, but definitely has teeth.
I'm looking for filthiness in lyrics and vocals, with a very organic feeling of hatred driving the guitars. Fucking depraved hatred. Murderous and mean, sans the satanic. Rabid.
I don't super care for Darkthrone but they're another good example. My bad if this is a shitty descriptor I'm a poet not a musician lol.