- "This symbol of the Negative Material Plane is inscribed upon a piece of human flesh. It smells of dust and corpse rot, yet it feels dry to the touch, like a serpent's tongue. As long as you carry it on your person, it will prevent your spells from going awry while on the Negative Material Plane."
This is an unused item present in the Planescape: Torment game files, but absent in-game. It is therefore impossible to acquire it, and it has no uses.