Dark Tutelage is a uncommon Enchantment card from Wilds of Eldraine: Enchanting Tales (WOT), collector number 28. Current market price: $0.20 (foil $0.34), TCGplayer market prices via Scryfall.
At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.