Essence of Antiquity is a uncommon Artifact Creature — Golem card from Murders at Karlov Manor (MKM), collector number 15. Current market price: $0.30 (foil $0.30), TCGplayer market prices via Scryfall.
Disguise {2}{W} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.) When this creature is turned face up, creatures you control gain hexproof until end of turn. Untap them.