The Colossal Dreadmaw is a rare Legendary Creature — Dinosaur card from Mystery Booster 2 (MB2), collector number 573. Current market price: $0.37, TCGplayer market prices via Scryfall.
Trample You may cast creature cards from your hand as though they were the card Colossal Dreadmaw. (They become Colossal Dreadmaws.)