Hollow Dark (Olyptia Supplement)
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 Plane of Fiends
This plane of existence is where all fiends and the evil spirits of the deceased who passed the Incorpreal plan are located. The Hollow Dark appears as a vast black void with rocky landmasses floating within the void where they exist. It is on this plane that the Olyptian Necromancers believe Muertix lives and from where they draw their real power. This plane is inherently evil.