Balduvian Trading Post is a rare Land card from Alliances (ALL), collector number 137. Current market price: $6.27, TCGplayer market prices via Scryfall.
If this land would enter, sacrifice an untapped Mountain instead. If you do, put this land onto the battlefield. If you don't, put it into its owner's graveyard. {T}: Add {C}{R}. {1}, {T}: This land deals 1 damage to target attacking creature.