Incubation Sac is a uncommon Artifact card from Phyrexia: All Will Be One (ONE), collector number 171. Current market price: $0.17 (foil $0.09), TCGplayer market prices via Scryfall.
This artifact enters with three oil counters on it. {4}, {T}, Remove an oil counter from this artifact: Create a 3/3 colorless Phyrexian Golem artifact creature token. Activate only as a sorcery.