Mistform Wakecaster is a uncommon Creature — Illusion card from Legions (LGN), collector number 48. Current market price: $0.09 (foil $1.25), TCGplayer market prices via Scryfall.
Flying {1}: This creature becomes the creature type of your choice until end of turn. {2}{U}{U}, {T}: Choose a creature type. Each creature you control becomes that type until end of turn.