Flat Ruins
Land (Rare)

Flat Ruins enters the battlefield tapped unless you sacrifice a colorless permanent.

Tap: Add W or U to your mana pool.

Tap: Add 2 to your mana pool. Put Flat Ruins on top of your library.

WU: Flat Ruins becomes a 2/1 white and blue Cleric creature until end of turn. It's still a land.

Aleksi Pollack