Stone of Tymora

The Stone of Tymora is an artifact sacred to the goddess of good fortune.

It bonds itself to the soul of a creature of it's own choosing, usually someone who is already naturally lucky. When in close proximity to the one it has chosen, that mortal can perform feats of extraordinary luck, such as taking a leap off of a tall building in a city, only to hit every piece of laundry out to dry on the way down, and then conveniently to land on something reasonably soft, thereby turning a certainly lethal fall into a mildly painful bump. Unfortunately, the nature of luck is that where there is good luck, there must also be bad, so when it alters the luck of it's wielder, somewhere another soul will experience an equal amount of bad luck.