The Temporal Anchor is a rare Legendary Artifact card from The Brothers' War Promos (PBRO), collector number 82p. Current market price: $0.29 (foil $0.42), TCGplayer market prices via Scryfall.
At the beginning of your upkeep, scry 2. Whenever you choose to put one or more cards on the bottom of your library while scrying, exile that many cards from the bottom of your library. During your turn, you may play cards exiled with The Temporal Anchor.