The Shadowfell was a dark reflection of the The Material World.The most striking and immediate impression a visitor to the Plane of Shadow experienced was the lack of color and light; no sun, moon, or stars adorned the vault of the inky black sky, and all things looked as if the color had leeched out, leaving nothing but black and white, which in the dimness were more like "dark black" and "light black". A light source only illuminated half the distance it normally would, flames and fires put out less heat, and spells that dealt with light or fire were less predictable and prone to failure, whereas shadow spells were enhanced. On the other hand, although it would not illuminate as far, any light source on the plane could be spotted at a distance of up to ten times its normal range of illumination, such was the contrast to the constant gloom, similar to a star in the night sky. Even a light source that only put out shadowy illumination, like a darkness spell or a lantern burning shadowlight oil, could be seen up to five times its range of illumination.
Gravity and time were the same on the Shadowfell as on the Prime, but the Shadowfell's landscape was a dark, twisted echo of what existed on the Prime. Upon entering the Plane of Shadow, the local features were usually quite similar: casting shadow walk in a forest put you in a shadow forest; casting it under water dropped you in a similar body of water, etc. But from that starting point, the landscape diverged rapidly away from the familiar, and on subsequent visits from the same starting point it diverged in different ways, making mapping the Shadowfell a useless endeavor. Landmarks were usually recognizable but altered in some bizarre way: buildings might be constructed in a different style, built with different materials, at a different location, and/or in any condition from dilapidated ruins to its normal appearance, for example, or otherwise strange and distorted. Similar sites were sometimes called "shadow-analogues
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