Sacred Foundry is a rare Land — Mountain Plains card from Guilds of Ravnica Promos (PGRN), collector number 254p. Current market price: $11.24 (foil $16.07), TCGplayer market prices via Scryfall.
({T}: Add {R} or {W}.) As this land enters, you may pay 2 life. If you don't, it enters tapped.