The Staff of Magnus is an ancient staff of considerable magical power. It belonged to Magnus, the eldest and most powerful wizard and the high king of their race.
When their race was being eradicated, the ancient Wizards hid the staff in Shangri-La to protect the world from its power. The staff is capable of greatly augmenting the magical powers of the wielder. Additionally, it can fire destructive bolts of lightning and can sense magic of similar origins.
The wizard Ambrose sent his son Bryant to retrieve the staff from Shangri-La after Arthur went there on a Magic School expedition. Despite its defenses, Bryant was able to escape with the staff and handed it to his father, who used it to vanquish the Tribunal.
Some time later, Ambrose used the staff to locate Atlantis and bring the island to the surface, as he desired Auger Shells to make his children immortal. He fought the Chosen until Arthur intervened and forced Ambrose to retreat.