Illuna, Apex of Wishes is a mythic Legendary Creature — Beast Elemental Dinosaur card from Ikoria: Lair of Behemoths (IKO), collector number 300. Current market price: $1.98 (foil $5.30), TCGplayer market prices via Scryfall.
Mutate {3}{R/G}{U}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Flying, trample Whenever this creature mutates, exile cards from the top of your library until you exile a nonland permanent card. Put that card onto the battlefield or into your hand.