The Reaper, King No More is a mythic Legendary Artifact Creature — Scarecrow card from Lorwyn Eclipsed Commander (ECC), collector number 4. Current market price: $0.56 (foil $0.32), TCGplayer market prices via Scryfall.
When The Reaper enters, put a -1/-1 counter on each of up to two target creatures. Whenever a creature an opponent controls with a -1/-1 counter on it dies, you may put that card onto the battlefield under your control. Do this only once each turn.