Elemental Plane of Shadow
The Plane of Shadow is a dimly lit dimension that is both coterminous to and coexistent with the Material Plane. It overlaps the Material Plane much as the Ethereal Plane does, so a planar traveler can use the Plane of Shadow to cover great distances quickly.
The Plane of Shadow is also coterminous to other planes. With the right spell, a character can use the Plane of Shadow to visit other realities. The Plane of Shadow is a world of black and white; color itself has been bleached from the environment. It is otherwise appears similar to the Material Plane. Despite the lack of light sources, various plants, animals, and humanoids call the Plane of Shadow home.
The Plane of Shadow is magically morphic, and parts continually flow onto other planes. As a result, creating a precise map of the plane is next to impossible, despite the presence of landmarks.
Within the Shadow Plane, Shadow Ellmere is widely recognized as a bastion of civilization in the region.