Duriel

Duriel is one of the "Lesser Evils" of Diablo lore and an antagonist in Diablo II, where he becomes an Act Boss - he is known as the Lord of Pain and rules over a section of Hell where demons are subjected to the most horrific forms of physical torture imaginable, so great is Duriel's thirst for pain that he is known to self-harm when their are no available souls to torture.