That Duergar looks just like my Dark Urge character, who was an Oath of the Ancients paladin until I decided to kill Philomeen and loot the Runepowder barrel from her after making the deal for the vial. (I had already freed Nere and finished everything else I could do in Act 1, and wanted to try out the Oath breaker Command Undead abilities on the Shadow cursed undead in Act 2.)