Ancient Cornucopia is a mythic Artifact card from The Big Score (BIG), collector number 16. Current market price: $3.65 (foil $6.15), TCGplayer market prices via Scryfall.
Whenever you cast a spell that's one or more colors, you may gain 1 life for each of that spell's colors. Do this only once each turn. {T}: Add one mana of any color.