Plane of Shadow
The Plane of Shadow is a late addition to the Great Wheel cosmology of Dungeons & Dragons, having originally existed in Advanced Dungeons & Dragons 2nd edition as the Demiplane of Shadow. Essentially, it is akin to the Ethereal Plane in that it lies coterminous with the Prime Material, but it is defined as looking like a lightless, colorless mirror of the Prime Material.
In the World Axis cosmology, conceptual aspects of the Plane of Shadow, the Negative Energy Plane and the Ethereal Plane would be amalgamated to create the Shadowfell.
The Plane of Shadow is a major part of Urban Arcana. It is the source of all the supernatural creatures that are appearing in the "real" world without memories of their homeworld and why planar transportation magic doesn't work here. This is referenced in the third edition The Manual of the Planes.
| Great Beyond of Pathfinder | ||||
|---|---|---|---|---|
| Heaven | Nirvana | Elysium | ||
| Astral Plane-Ethereal Plane | ||||
| Axis | Material Plane-Boneyard | Maelstrom | ||
| First World-Inner Planes-Shadow Plane | ||||
| Hell | Abaddon | Abyss | ||