Twilight Knoll
Land-Swamp Mountain (Rare)

(Tap: Add B or R to your mana pool.)

When Twilight Knoll enters the battlefield, sacrifice it unless you pay R.

BB, Tap, Sacrifice Twilight Knoll: Put a -1/-1 counter on target creature.

2, Tap: Target land becomes a 3/3 red Ogre creature until end of turn. It's still a land.

Ron Pollack