Takenuma, Abandoned Mire is a rare Legendary Land card from Kamigawa: Neon Dynasty Promos (PNEO), collector number 278p. Current market price: $17.80 (foil $23.71), TCGplayer market prices via Scryfall.
{T}: Add {B}. Channel — {3}{B}, Discard this card: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.