Moradin, the Allhammer

Moradin costs {x} less to cast, where X is the
number of permanents you control that entered
the battlefield this turn.
Whenever an opponent is dealt damage, you may
exile target creature you control. If you do, reveal
cards from the top of your library until you
reveal a nonland permanent card. Put that card
onto the battlefield and the rest into your
graveyard. You gain life equal to the number of
cards revealed this way.