Rootwater Grave
Land-Island Swamp (Rare)

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

Rootwater Grave enters the battlefield tapped.

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

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

Aleksi Walker