Dirgur Nemesis is a common Creature — Serpent card from The List (PLST), collector number DTK-51. Current market price: $0.49, TCGplayer market prices via Scryfall.
Defender Megamorph {6}{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.)