Jungle Swamp
Land (Rare)

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

BG, Tap: Add GG, GB or BB to your mana pool.

3: Jungle Swamp becomes a 2/2 black Rat creature until end of turn. It's still a land.

Ron Briclot