Duskmantle Seer is a rare Creature — Vampire Wizard card from Conspiracy: Take the Crown (CN2), collector number 202. Current market price: $0.28 (foil $0.50), TCGplayer market prices via Scryfall.
Flying At the beginning of your upkeep, each player reveals the top card of their library, loses life equal to that card's mana value, then puts it into their hand.