Tranquil Cave
Land (Rare)

At the beginning of your end step, if you didn't cast any spells this turn, Tranquil Cave deals 1 damage to you.

Tap: Add R or W to your mana pool. Tranquil Cave deals 2 damage to you.

1W: Tranquil Cave becomes a 0/4 red and white Soldier Kor creature with defender until end of turn. It's still a land.

Steve Spencer