Dungeons and Dragons
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. Legend has it that an otherworldly dimness arose around the remnants and tatters of the raw stuff of creation. Over time, these shadows coalesced and assumed a form similar to the natural world, but darker, more ominous, and thrumming with a strange and unexpected power. 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 souls journey before moving onto the unknown. For this reason, the Shadowfell draws the attention of any with an interest in death. The power and allure of this place even drew the Raven Queen from the Astral Sea to take residence among the spirits, to govern them, and to monitor their movements as they await the inexorable pull of dissolution.
A place of deep shadows, of familiar yet alien landscapes, of vistas that snatch the breath, and of mind-rending visions, the Shadowfell is the gloomy reflection of the natural world. It is a plane dimmed and dulled by a pervasive and insidious pall. The home of the dead, the realm of the forsaken, a haven of the lost and the twisted, the birthplace of wretched creatures famous for their grief and sorrowthe Plane of Shadow is all this and more.
The Feywild reminds the traveler of the mortal world, but exaggerates its verdant splendor. The Shadowfell is similarly reminiscent, but the reflection is far different. Familiar landmarks, peoples, and places are changed, as if born from half-remembered nightmares or perverted by fear and doubt. Perils abound in the Shadowfell. Still, the allure of lost treasures, strange mysteries (including those of death), and alien vistas draw the bold and foolish alike to test their mettle against the forces of darkness that rule this chilling plane.
For all the Shadowfells dismal reputation, it does have bright spots where those who fight against the malaise and the chill live almost ordinary lives. In fact, for many visitors to the Shadowfell, the plane has more in common with the natural world than it has differences. This is both comforting and disturbing.