You could really take your pick of Vampire the Masquerade baddies.
Ur-Shulgi, for instance, who looks like a charred corpse, has led multiple genocides, is directly referred to as "violence incarnate," and doesn't seem to have a goal beyond exterminating everything he considers unclean. Depending on who you ask, that may very well be damn near everything, period.
Or Sascha Vykos, who... to call them a torturer is like saying Michelangelo kinda knew how to paint. Vykos is a monster in every sense of the word, and cruelty is both method and goal in a lot of their schemes.