Thiago, the Quiet Guardian

Flying, vigilance
Whenever a creature with defender enters the battlefield under your control you may pay {2}. If you do, you may exile a card from your
hand face down. You may cast the exiled card as
though they had flash. Whenever you cast an
exiled card you may draw a card.
Enemies blood may run down the walls, and he'll still
be waiting to protect its kind