Crater Fields
Land (Rare)

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

Tap: Add R or W to your mana pool.

Put Crater Fields on top of your library: Add 1 to your mana pool.

1W: Crater Fields becomes a 0/4 red and white Giant creature with defender until end of turn. It's still a land.

Allan Argyle