The Shadowfell is the dark echo of the mortal world, a twilight realm that exists “on the other side” of the world and its earthly denizens. This murky land spawned beings of its own and drew others from different parts of the cosmos. It came to be filled with a diverse population of creatures, fair and foul.
The Shadowfell is more than just a mirror, even as darkly cast and twisted as it is. This plane is the destination of souls loosed from their bodies. It is the domain of the dead, the final stage of the soul’s journey before moving onto the unknown. For this reason, the Shadowfell draws the attention of any with an interest in death.
Creatures sometimes perceive time differently in the Shadowfell from how they do in the world. Rather than passing with the rise or fall of the sun, time moves based on the gloom infecting one’s mind. A visitor to the Shadowfell might feel as though days or weeks have passed, when in fact years have gone by on his or her native plane.
Places where the boundary between the world and the Shadowfell are thin are known as shadow crossings. Some intersections are naturally occurring, the result of ancient planar conjunctions or catastrophes. These crossings often occur in low-lying, deeply shadowed spots. Other junctions form in places where the forces of death are prevalent—graveyards, battlefields, and other places that bore witness to mass death.
known Shadow crossings:
It is believed there are Shadow crossings in Syraad, but this is unconfirmed.