He and his followers were exiles from the Abyss. If destroyed in the Prime Material Plane, they would slowly reform, only to be exiled once again. Due to this, they were unable to gate in demons more powerful than manes (which transformed into shadows and ghasts), and because of this, the forces of Hellgate Keep had few actual demons included in their forces. Grintharke constantly sought to appease his masters in one form or another with the hopes of regaining a standing in the Abyss.
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