The Umbra, also called the Spirit World, the Shadow, or the Velvet Shadow, is a realm existing alongside and yet separate from the material world.
umbra: Latin: shadow. A complete shadow (as of the Moon) within which the source of light (the Sun) is totally hidden from view.
The term "Umbra" is generally used, particularly by werewolves, to refer specifically to the "Spirit Wilds," or Middle Umbra. However, there is more to Umbral cosmology than this.
Some, like the Void Engineers, consider the Umbra an alternate or parallel dimension, universe, or reality, despite it being, technically, occupying the same physical space as the Earth.
The Gauntlet
Separating the Earth from the Umbrae is a metaphysical "membrane" known as the Gauntlet. Some humans almost manage to get close to the Gauntlet in times of bliss, meditation, or creativity; this state is known as the Periphery.
The Gauntlet is thinner in places such as a haunted graveyard or the open wilderness, and thicker in places such as laboratories and shopping malls. The strength of the Gauntlet in a given area determines the ease with which one can cross it, or "step sideways." The Gauntlet is usually treated as a single phenomenon, when it is actually sort of three Gauntlets in one: one separating the Earth from the Astral Plane, one protecting it from the Spirit Wilds, and one blocking access to the Underworld and the horrors that lie within. The latter Gauntlet is also referred to as the Shroud by wraiths, and as the Stormwall by agents of the Orpheus Group.
Penumbra
Directly "overlapping" the material world is a portion of the Umbra known as the the Penumbra. The Penumbra mirrors physical reality, but reality as it is "supposed" to be. Though divided, the two were once joined. The spirit world still touches the material one, for were it gone completely, Earth could not sustain life.
Powerful actions on the physical plane send emanations across the spirit world. The most powerful of these psychic waves ripple past the Penumbra into the Near Umbra, where they have the potential to create whole realms. Such Realms often form based around a single idea or collection of legends. For example, the Nazi concentration camps founded throughout the course of World War II created vast hellholes with pits that lead to Malfeas or the Atrocity Realm, while the atomic bombing of Hiroshima and Nagasaki sent the psychic reflection of dead zones into the Thousand Hells of the Yama Kings.
In the Penumbra, a toxic waste dump site will swarm with malevolent Banes, while a city will be covered in the cobwebs woven by Pattern Spiders. A grove of trees will stand taller and wilder, and a volcano eruption or the flaming chimneys of factories could give birth to Fire Elementals.
The appearance of the Penumbra seems to be based partially on the viewpoint of the one bearing witness to it. Werewolves will see it in a more animistic fashion, with an immense Moon dominating the sky (the Sun, conversely, tends to be much smaller), with everything from trees and rocks to the very stars themselves being represented by a spirit. Some mages may see it more as representing ideals and concepts rather than spirits. Other mages (and the rare vampire who makes it there) will see things in a state of decay: a swollen red sun shining sickly light down on crumbling buildings and the rusting husks of cars and trucks.
An uninformed observer may assume, based on description, that there are three different Penumbrae, one for each Umbra. This is a mistaken assumption, however: if three different travellers arrive in the Penumbra, each viewing a different "facet,” they are still able to see and contact each other and interact just as easily as they would in the physical world. Despite the varying perspectives of those who witness it, there is truly only one Penumbra.
