Castle Locthwain is a rare Land card from Throne of Eldraine (ELD), collector number 389. Current market price: $11.17 (foil $34.47), TCGplayer market prices via Scryfall.
This land enters tapped unless you control a Swamp. {T}: Add {B}. {1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.