Hidden Dragonslayer (69) [Murders at Karlov Manor Commander]

Lifelink Megamorph {2}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.) When this creature is turned face up, destroy target creature with power 4 or greater an opponent controls.