Avendar

The Void is nothing, the rift of pure emptiness that encompasses and embraces the Prime Material. It is the demesne and corpus of Ashur, who is also emptiness. It is a space of pure entropy, the end of time, and utterly inimical to life.

Many places exist within the Void, and many are populated by demons. A demon is nominally any denizen of the Void, whether native or transformed. Many different kinds of demonic species and varieties exist of varying levels of power and hostility towards mortals and the Prime Material. Void magicians frequently summon and bind demons to various ends with the use of rites that pierce the Silver Veil, the planar barrier that isolates the Prime Material. The nature of those pacts varies, as does the attitude bound demons have towards their binders, though it is rarely positive.

Thirteen Saints of Ashur

The thirteen Lords of the Void are god-like in strength within their spheres of influence. The names and natures of the Saints of Ashur may change, but there are always thirteen, and Ashur is always the thirteenth.