Gandalf, Westward Voyager is a mythic Legendary Creature — Avatar Wizard card from Tales of Middle-earth Commander (LTC), collector number 463. Current market price: $3.58 (foil $5.07), TCGplayer market prices via Scryfall.
Whenever you cast a spell with mana value 5 or greater, each opponent reveals the top card of their library. If any of those cards shares a card type with that spell, copy that spell, you may choose new targets for the copy, and each opponent draws a card. Otherwise, you draw a card. (A copy of a permanent spell becomes a token.)