Stay Hidden, Stay Silent is a uncommon Enchantment — Aura card from Duskmourn: House of Horror (DSK), collector number 291. Current market price: $0.17 (foil $0.14), TCGplayer market prices via Scryfall.
Enchant creature When this Aura enters, tap enchanted creature. Enchanted creature doesn't untap during its controller's untap step. {4}{U}{U}: Shuffle enchanted creature into its owner's library, then manifest dread. Activate only as a sorcery.