From the back of the book...
Mages kill each other to become the Magister.
The Magister of Mystra is one of the most mysterious - and misunderstood - beings in the Forgotten Realms setting. Some say the Magister is simply the most powerful mortal mage in all of Toril. Perhaps, but there is something more, something unique, about being so touched by the Mother of All Magic.
The mages of Faerun roll up their sleeves and craft the spells and items that they hope will empower them to win the office of the Magister. A few will succeed. More will wish they'd never taken up magic in the first place.
Here at last, one can learn all the secrets, abilities, and sacred duties of the Magister. Plus, discover the fate of Lady Noumea and the identity of her successor as Magister. Also, read guidelines on how a PC mage might become the Magister.
This book holds the history of the office, new powers, spells, magic items, a roster of select Magisters from the past, and guidelines on how to incorporate the Magister into your campaign.
One Magister became a god; others have hoped to.