The Dawning Archaic is a mythic Legendary Creature — Avatar card from Secrets of Strixhaven (SOS), collector number 289. Current market price: $1.78 (foil $3.22), TCGplayer market prices via Scryfall.
This spell costs {1} less to cast for each instant and sorcery card in your graveyard. Reach Whenever The Dawning Archaic attacks, you may cast target instant or sorcery card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.