Nuflov, Voodoo Fanatic

Shroud, Trample
Shroud, Trample Creatures you control attack each turn if able and can't be sacrificed during your turn.
At the beginning of your upkeep, choose an opponent at random. That player controls you during your turn. Whenever mana empties from your pool, if that mana was not used to cast a spell or pay for an ability, the player controlling you loses that much life.