Twilight Heights
Land-Plains Swamp (Rare)

(Tap: Add W or B to your mana pool.)

Twilight Heights enters the battlefield tapped unless you reveal an artifact land card from your hand.

Tap, Sacrifice a Swamp: Add BB to your mana pool.

2, Tap: Target land becomes a 3/3 white Knight Citizen creature until end of turn. It's still a land.

Douglas Grant West