Glacial Catacombs
Land (Rare)

Whenever Glacial Catacombs becomes tapped, it deals 1 damage to you.

Tap: Add U to your mana pool. If you played a land this turn, Add B to your mana pool instead.

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

Steve Critchlow