The Cruelty of Gix is a rare Enchantment — Saga card from Dominaria United Promos (PDMU), collector number 87s. Current market price: — (foil $3.34), TCGplayer market prices via Scryfall.
Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.) I — Target opponent reveals their hand. You choose a creature or planeswalker card from it. That player discards that card. II — Search your library for a card, put that card into your hand, then shuffle. You lose 3 life. III — Put target creature card from a graveyard onto the battlefield under your control.