Escaped Experiment is a common Artifact Creature — Phyrexian Beast card from Phyrexia: All Will Be One (ONE), collector number 48. Current market price: $0.12 (foil $0.17), TCGplayer market prices via Scryfall.
Whenever this creature attacks, target creature an opponent controls gets -X/-0 until end of turn, where X is the number of artifacts you control.