Dungeons & Dragons has taken brave adventurers to magical and unexpected places with just a hint of reality woven into the fabric of their creation. The Shadowfell is a plane parallel to the Prime Material, in conjunction with the Feywild. If the Feywild is the Prime Material's dream reflection, the Shadowfell is a mirror of its darkness, drawing from the shadows and gloom in a way that makes it impossible to forget that, where there is light and life, there is also darkness and decay.

Upon arriving in the Shadowfell, one of the most noticeable aspects of its landscape is the lack of color and light. There's just an endless black sky devoid of sun, moon and stars that stretches overhead. In the lingering gloom, it becomes apparent that this is a world in tones of black, gray and white.

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Because the Shadowfell is a land heavily cloaked in shade and darkness, using magic that produces light and fire can have unpredictable results. On the other hand, spells that produce or enhance shadows thrive, even becoming more powerful than they might be on other planes. It has been said that travelers to the Shadowfell, no matter how long they stay there, never feel bodily warmth, a cold chill always lingering and creating discomfort.

Much as the Feywilds mimics light and abundant life, the Shadowfell reflects the twisted shadow and darkness of the landscape and design of the Prime Material. Unfortunately, the nature of and changeability of shadows makes mapping the Shadowfell all but impossible, as repeated visits often revealed that locations, buildings and landscapes were slightly altered each time, making it difficult to be certain one was in the same place.

The Shadowfell and the beings who dwell there are composed of a material known as "shadowstuff," which some believe to be leftover remnants of creation. Illusionists and magic-users who work in shadow and deception have been known to draw upon shadowstuff when casting their spells, in essence pulling a small piece of the Shadowfell into whatever plane of existence they are currently on to enhance their magic.

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Small demiplanes known as the Domains of Dread exist all across the Shadowfell and are often used to trap evil entities so the plane itself can feed on their essence. One such Domain of Dread is Barovia, where the legendary vampire Count Strahd Von Zarovich was trapped by the Dark Powers.

Home to numerous species, the most prominent entities who dwell in the Shadowfell are mysterious undead beings called shadows. Shadow dragons and shadow mastiffs can also be found there, along with a host of dark, terrifying creatures like wraiths, spectres, darkweavers and shadow demons. There are also a number of humanoid natives, including gnomes, humans, halflings and beings known as Shadar-Kai.

Over the years, the Shadowfell's association with different deities has fluctuated as D&D expanded or revised their mythos. Master of all Thieves and Lord of Shadows, Mask, once had a realm there called Shadow Keep, while Mistress of Night and Lady of Loss Shar had a palace there known as the Palace of Loss. Shar eventually moved out of the Palace of Loss and into the Tower of Night in the Astral Sea, leaving a gaping hole that became known as the Foundation of Loss.

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Domains of the Draconic God of Death, Null, were also said to exist simultaneously in the Shadowfell and Carceri and the Outlands. In Fifth Edition, however, the Raven Queen has been named ruler of the Shadowfell. Though her controversial nature has been altered through the years, she's the one people now think of when the Plane of Shadow comes to mind. Even the Shadar-Kai worship her as their patron goddess.

The Fortress of Memories was one of the Raven Queen's realms, a reference to her fascination with the collection of memory fragments. She was so obsessive in her collection of such things that many believed she was actually insane, driven so by a desperate need to ensure that she herself was never forgotten. She made it her purpose, however, to help the fretful face their fears and pain, allowing them to embrace death as a natural part of life.

This purpose has made her an enemy to those who would pervert death through necromancy. Vecna and Orcus are two of her best-known rivals. There's a deep hatred between them that drives the Raven Queen's followers to do all in their power to exterminate those who follow her enemies.

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Much like the Fey Crossings travelers use to access the Feywild, there are numerous Shadow Crossings in places like cemeteries, crypts and bloody battlefields fraught with tumultuous memories of death. Shadow Crossings are fleeting, never lasting for long once they open, but those capable of casting Planeshift who possess a tuning fork attuned to the Plane of Shadow can come and go as they please.

A place of deep depression and gloom, it is said that those who enter the Shadowfell are never the same once they leave. The eerie chill that clings to their skin and infiltrates their bones lingers long after they depart, as does the melancholy and darkness of the soul. The Shadowfell can corrupt the spirits of those who dare to travel there, making it one of the most dangerous planes of existence for adventurers to visit.

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