Mangara's Tome is a rare Artifact — Book card from Mirage (MIR), collector number 309. Current market price: $3.49, TCGplayer market prices via Scryfall.
When this artifact enters, search your library for five cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library. {2}: The next time you would draw a card this turn, instead put the top card of the exiled pile into its owner's hand.