From DivNull RPG
Vortigern searches for this stone, created by Guh’shelluh. He has made a deal with Tanador to find it, claiming that Tanador “will know it”. Vortigern wants to know how it is guarded and what is its nature. It is currently known to be fixed into a talisman.
People keep it close. Stories are of the order of: “The possessor of the stone went up the hill with the stone. When he came down things were different.”
The stone is an amplifier. If you know to much about it, it won’t permit you to do certain things.
Vortigern believes that the stone is held by the Bruckenbrod Thieves Guild. They have counter-measures he cannot pass easily. They need to be passed using deception, guile and wit.