Kicker-Return a creature you control to its owner's hand. (You may return a creature you control to its owner's hand in addition to any other costs as you cast this spell.) If Arctic Merfolk was kicked, it enters the battlefield with a +1/+1 counter ...
Kicker-Sacrifice two lands. (You may sacrifice two lands in addition to any other costs as you cast this spell.) Target player discards two cards. If Bog Down was kicked, that player discards three cards instead.
Flying.When Cavern Harpy enters the battlefield, return a blue or black creature you control to its owner's hand.Pay 1 life: Return Cavern Harpy to its owner's hand.