The Witch Doctor

When an opponent's life total reaches 20 or lower, reveal this. Put a witchery counter on it.
When a non-deity opponent dies, remove all witchery counters from this. That player's life total becomes 40, they lose all poison counters, and they shuffle their graveyard into their library. That player looks at two 'satanic worshiper' cards, and picks one. That player becomes that role.