Hearken now to a tale of the Realms, ye jaded lords, ladies, and gentles. Oh, it is a grand tale, to be sure. It has murder, and magic, and lovemaking-and, as usual, you'll misunderstand every word of it.

Be not angry, mind; the fault's not with you, or me. Life's like that, you see. Lhaeo Rhindaun, Scribe to Elminster

There is a slim, dark and dusty tome few have ever read…

It lies hidden beneath a rune-graven flagstone under the circular table in the innermost chamber of Candlekeep. This tome is called The Book of Mysteries, and it sets forth all that the writer-whose name, of course, has been forgotten-knew of the nature and powers of Mystra, the goddess of magic.

Chief among the book's secrets of Realmslore is the matter of Mystra's essence or vitality. As mistress of magic, her power is far greater than that of the other gods of Toril. Yet, to mortals at least, it seems not so. Therein lies the secret.

Throughout history, as long as there have been gods, and people of Toril to worship them, the essential power of Mystra has been held not only by the goddess herself, but by a self-willed, loyal demigod-Azuth, who was the greatest archmage of his day-and a handful of mortals.

These mortals cannot wield what they hold of Mystra's power, but they can withhold it, even from the goddess herself. This self-will, and the mortals' often widespread travels, keep Mystra from ruling all of Realmspace and prevent any other being from doing so through her. Should Mystra ask to use the power that they hold, each of the mortals can willingly let it pass into her, but they cannot be coerced into doing so. At the moment when one of these mortals dies, the power that he or she holds passes into the greater essence of life in Toril, returning to Mystra slowly but usable by none except her.