Gaze of the Gorgon is a common Instant card from Ravnica: City of Guilds (RAV), collector number 246. Current market price: $0.11 (foil $4.48), TCGplayer market prices via Scryfall.
({B/G} can be paid with either {B} or {G}.) Regenerate target creature. At this turn's next end of combat, destroy all creatures that blocked or were blocked by it this turn.