Fireglass Mentor is a uncommon Creature — Lizard Warlock card from Bloomburrow (BLB), collector number 213. Current market price: $0.23 (foil $0.29), TCGplayer market prices via Scryfall.
At the beginning of your second main phase, if an opponent lost life this turn, exile the top two cards of your library. Choose one of them. Until end of turn, you may play that card.