The Ancient One is a mythic Legendary Creature — Spirit God card from The Lost Caverns of Ixalan Promos (PLCI), collector number 222s. Current market price: — (foil $4.13), TCGplayer market prices via Scryfall.
Descend 8 — The Ancient One can't attack or block unless there are eight or more permanent cards in your graveyard. {2}{U}{B}: Draw a card, then discard a card. When you discard a card this way, target player mills cards equal to its mana value.