Thoon

Thoon is perhaps a deity or some other entity which is venerated by a specific group of Mind flayers. But since it isn´t known what Thoon exactly is, it could be a guiding philosophy just as well.

History
Not long after the last arrival of an avatar of Ilsensine in Oryndoll (maybe in 1358), some Mind Flayers of the Loretaker creed journeyed to the Cavern of Thought in the Deep Caverns. It isn´t known if they arrived there or went to some other place, most likely the Far Realm. When they came back to Oryndoll, they proclaimed the belief in Thoon - a doctrine for which they were outcast by the clergy of Ilsensine. The "Mind Flayers of Thoon" now travel the Underdark, where they spread the philosophy of Thoon. Along the way, they search for a mysterious substance they call "quintessence", which can be found in creatures as well as in raw materials.

Clergy
Thoon disciples have access to the Evil domain and War domain and wield Heavy flails.