Castle Locthwain is a rare Land card from Throne of Eldraine Promos (PELD), collector number 241s. Current market price: — (foil $5.98), 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.