Gutmorn, Pactbound Servan

Flying, deathtouch
Whenever Gutmorn, Pactbound Servant enters
the battlefield, each player discards a card.
Whenever an opponent discards a card during
your turn, exile that card. You may cast that card
for as long as it remains exiled, and you may
spend mana as though it were mana of any type
to cast it.