Mystic Redaction is a uncommon Enchantment card from Modern Horizons 2 (MH2), collector number 53. Current market price: $0.22 (foil $0.31), TCGplayer market prices via Scryfall.
At the beginning of your upkeep, scry 1. Whenever you discard a card, each opponent mills two cards. (They put the top two cards of their library into their graveyard.)