Faceless Monstrosity

Deathtouch, Skulk
Whenever Faceless Monstrosity deals combat damage to a player or planeswalker, exile a
card from your hand facedown.
You may cast facedown cards in exile. If you
do, pay 3 life instead of paying it's mana cost. If there is X is the mana cost, sacrifice a creature. X is equal to the sacrificed creatures mana cost.