Sorin's Guide is a rare Creature — Vampire card from Core Set 2020 (M20), collector number 292. Current market price: $0.25, TCGplayer market prices via Scryfall.
When this creature enters, you may search your library and/or graveyard for a card named Sorin, Vampire Lord, reveal it, and put it into your hand. If you search your library this way, shuffle.