Haka, Corpse Collector

Haka can be cast from your graveyard and
only your graveyard.
If Haka is in your opening hand, you may
put him into your graveyard, if you do,
put the top three cards of your library
into your graveyard, then gain 3 life.
{t}; exile a creature card from your graveyard;
deal four damage to any target.