Vhyridaan the Mad

Vhyridaan the Mad was a male half-elf mage who had his soul trapped inside a stone.

History
Exiled from Myth Drannor, Vhyridaan was self-taught in the ways of High Magic. He tried to store his knowledge in a kiira, but failed—the stone absorbed not only his knowledge but his body and soul completely, as well as the one magic item he had with him, a ring of spell turning. His soul remained trapped inside the stone thereafter, becoming the mantle stone of Vhyridaan, a unique ioun stone.

After several owners, the mantle stone fell into the clutches of Aulmpiter, the nycaloth commander of the Army of Darkness during the Weeping War. At the Fall of Myth Drannor in 714 DR, during the Bane's Duel, Aulmpiter and Captain Fflar Starbrow Melruth dueled to the death. Vhyridaan and the mantle stone were presumed destroyed, either sundered by Fflar or in the explosion that annihilated both combatants.

Powers
Vhyridaan lived on as a sentient magical item in the mantle stone. He could communicate mind-to-mind when in contact with the stone's owner. He had no ego and no power to possess the owner, however. Thanks to this sentience, the stone actively avoided efforts to grab or attack it. Furthermore, if the stone hovered over an owner's spellbook as they studied and memorized their spells, then Vhyridaan could memorize these spells as well. However, he would almost certainly learn the same spells.