The Thieves of Waterdeep
A lucky Charm
This magical stone is typically a bit of rough polished agate or similar mineral. Its possessor gains a 5% where applicable) on all dice rolls involving factors such as saving, slipping, dodging, etc.—whenever dice are rolled to find whether the character suffers from some adverse happening. This luck does not affect attack and damage rolls or spell failure dice.
Additionally, the luckstone gives the possessor a +/- 1% to 10% (at owner’s option) on rolls for determination of magical items or diversion of treasure. The most favorable results will always be gained with a stone of good luck.
Sir Lanceabit tripped on this stone and knocked himself unconscious. This directly resulted in Eddard finding him and eventually offering him a job. Sir Lanceabit kept the stone as his lucky charm. Which is lucky because it actually IS a lucky charm.