Radagast the Brown is a mythic Legendary Creature — Avatar Wizard card from Tales of Middle-earth Promos (PLTR), collector number 184s. Current market price: — (foil $16.39), TCGplayer market prices via Scryfall.
Whenever Radagast or another nontoken creature you control enters, look at the top X cards of your library, where X is that creature's mana value. You may reveal a creature card that doesn't share a creature type with a creature you control from among those cards and put it into your hand. Put the rest on the bottom of your library in a random order.