Forbidding Watchtower is a uncommon Land card from Urza's Legacy (ULG), collector number 140. Current market price: $0.44 (foil $10.25), TCGplayer market prices via Scryfall.
This land enters tapped. {T}: Add {W}. {1}{W}: This land becomes a 1/5 white Soldier creature until end of turn. It's still a land.