Rot-land
Land (Rare)

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

Tap: Add W or B to your mana pool.

Sacrifice Rot-land: Add W or B to your mana pool.

WB: Rot-land becomes a 2/1 black and white Wizard creature until end of turn. It's still a land.

James Walker