Amulet of Yendor

The Amulet of Yendor is the most powerful known artifact of unknown origin and the object of many a (failed) quest. It is said to possess powers which mere mortals can scarcely comprehend, let alone utilize.

History
After the creation of the Universe, the cruel god Moloch rebelled against the authority of his pantheon's leader, Marduk. Moloch stole from Marduk the most powerful of all the artifacts of the gods, the Amulet of Yendor, and he hid it in the dark cavities of Gehennom, the Under World, where he now lurks, and bides his time. The amulet is currently rumored to be somewhere beyond the Valley of Gehennom, deep within the Mazes of Menace. The gods will grant the gift of immortality to the adventurer who can deliver it from the depths of Moloch's Sanctum and offer it on the appropriate high altar on the Astral Plane.