Valiant Changeling is a uncommon Creature — Shapeshifter card from Modern Horizons (MH1), collector number 34. Current market price: $0.22 (foil $4.06), TCGplayer market prices via Scryfall.
This spell costs {1} less to cast for each creature type among creatures you control. This effect can't reduce the amount of mana this spell costs by more than {5}. Changeling (This card is every creature type.) Double strike