Bitterblossom is a mythic Kindred Enchantment — Faerie card from Wilds of Eldraine: Enchanting Tales (WOT), collector number 27. Current market price: $31.83 (foil $34.60), TCGplayer market prices via Scryfall.
At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.