Reaver of Kozilek

Manareave 3 (Whenever this creature attacks, opponent must tap 3 mana cards, which untap during your untap step)
{2}{t}: Change Manareave to Annihilator. Can be activated whilst Reaver of Kozilek has Annihilator to change back to Manareave.
Superflouism is the only thing the Eldrazi understand.