Flagstones Crypt
Land-Plains Swamp (Rare)

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

Flagstones Crypt enters the battlefield tapped unless you sacrifice a multicolored permanent.

W, Tap, Sacrifice Flagstones Crypt: Prevent all combat damage that would be dealt this turn.

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

Eric Chippy