Plebosh

"Okay, listen. I'll say it again. Concentrate. Cooooncentrate" - Plebosh speaks to Cabian in their shared mind.

At a Glance
Cabian Nolash was the neglected stepchild of the Nolash family of Bravaria. Lame-minded, his difficulties learning made him a failure in the eyes of his father. As fate would have it, escaping from The Realm of Dreams the elder-and-bookish Kalashtar spirit Plebosh leapt into Cabian's body, trapping the two together. It was through their combined union that the pair learned focus and dedication.

Dreamer's Ladder
Plebosh was killed by Koshmar's minions in a rescue attempt of the gnome bard Pribill.