The Wheel (3.5e Equipment)
From D&D Wiki
The Wheel: The Wheel is a technological marvel, perfectly circular and wonderfully balanced you can push it across a surface and watch it roll gracefully.
Any person holding the wheel must make a DC25 will save or be unable to discard the wheel. You can put The Wheel away, but must be carrying it at all times, if you are separated from The Wheel for any longer than 1 minute you take 1 point of constitution damage, per minute. When anyone declares an attack they roll their attack die normally but find that they are holding The Wheel when they must roll damage.