William Murderface (voiced by Tommy Blacha) is Dethklok's bassist. He plays a Gibson Thunderbird Studio 5-string. He has brown hair, green eyes, a heavy lateral lisp and a diastema. Murderface's father killed his wife with a chainsaw before turning it upon himself in front of Murderface in a grisly murder-suicide. Murderface is "a self-hating bass player who's always trying to act like he's more important than he is," in part because his bass playing is usually mixed out completely.
Brendon Small describes Murderface as "thin-skinned and incredibly sensitive and just wants to be accepted constantly but can’t get that because he’s such a dick and pushes people away". Murderface's voice was originally achieved by Tommy Blacha putting paper towels inside his mouth when voicing the character, but he has since refined his technique to avoid the paper towels.