Mighty Breach

As an additional cost to cast Mighty Breach, you
may reveal a Kraken, Leviathan, Fish, Shark or Serpent creature card from your hand.
Return target creature to its owner's hand. If
you revealed a card as you cast this spell, you may
deal damage equal to the revealed card's power
to the target creature instead. The revealed card
costs {x} less to cast, where X is the amount of
damage the revealed card dealt this turn, to a
minimum of 3.