River Wreckage
Land (Rare)

When River Wreckage enters the battlefield, sacrifice it unless you pay 2 life.

Tap: Add 1 to your mana pool.

Tap: Add U or B to your mana pool. Each opponent gains 1 life.

UB: River Wreckage becomes a 2/1 blue and black Merfolk creature until end of turn. It's still a land.

Eric Critchlow