Silumgar Spell-Eater is a uncommon Creature — Snake Wizard card from Dragons of Tarkir (DTK), collector number 77. Current market price: $0.11 (foil $0.24), TCGplayer market prices via Scryfall.
Megamorph {4}{U} (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, counter target spell unless its controller pays {3}.