Bog Conclave
Land (Rare)

When Bog Conclave enters the battlefield, you lose 1 life unless you reveal a Black card from your hand.

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

2: Bog Conclave becomes a 2/2 black Cleric creature until end of turn. It's still a land.

Mark Nielsen