The Planes of Samru


Otherplanar Races

On Samru there are understood to be 4 planes. They are bound by the caitanya matrices, also known as the eldren patterns. The caitanya matrices are laid over the darkflux, the raw material of the multiverse, like brocade patterns woven into cloth, giving the seething darkflux shape and texture. The masters of the darkflux, and greatest of all manipulators of the matrices, are those forces called the avatarchs, whose power extends over all four planes:

Attrahent is the mortal plane, the plane in which the planets and stars exist, and all beings that live in the shadow of death.
Adumbra is the shadowed plane, the plane of astral beings.
Illume is the luminous plane, the plane of ethereal beings.
Attrament is the secondary material plane, the plane of the avatarchs, the mendicants, and the dead.

This is an oversimplification. Scholars know better.

Attrahent is otherwise known as the "prime material plane," a universe of phlogiston, crystal spheres, wildspace and planets. Within the plane called Attrahent are those systems called the Infinite Spheres, that move slowly through the irridescent void with the celestial dragons, the voiddrakes and the various other soujourners. Each one of the Infinite Spheres appears as a sphere of crystal woven into the darkflux, containing within its fragile shell planets and moons and other such celestial bodies.
Adumbra is sometimes the astral plane, the shadow plane, or the negative material plane; Illume sometimes the ethereal plane, or the positive material plane, and Attrament a catch-all for the outer planes. This loose usage is more than sufficient for day-to-day needs, but scholars of the planes have a much more specialized understanding.
Attrahent suffices as a term for the prime material plane, although the term "prime material plane" is often misused as a synonym for "planet" and should therefore be treated with caution. In fact, there are very many planets within the prime material plane.
The Ethereal Plane (Illume) is a broad term for the hyperfield that binds together Attrahent. The Inner Planes can also be reached through Illume. Illume is traditionally divided into the "Border Ethereal," that wavelength closely synchronized with Attrahent and most easily accessible by certain spells, and the "Deep Ethereal."
The term "Deep Ethereal" is actually misleading. The so-called "Deep Ethereal" is actually a set of wavelengths spanning higher and lower frequencies between Illume and Adumbra. They tend to be called demiplanes, although the term metaplanes would be better. These include the demiplanes Shadow, Time (also, the Chronoscape), Imprisonment (also, Dread, Ravenloft) and Dreams (also, the Onieroscape). Most gating spells cut through the Ethereal plane and cross the Chronoscape, permitting "instantaneous" movement across Attrahent.
The Astral Plane (Adumbra) is a broad term for the hypofield that binds together Attrahent. The Outer Planes can also be reached through Adumbra. Adumbra and Illume do not normally touch, unless a wormhole opens through the metaplanes and/or the prime.
Interestingly, various materials prevent passage to and from Illume and Adumbra. In particular, Illume cannot be reached through most solid objects, particularly dense materials (usually gold or lead) and living creatures. Adumbra, on the other hand, cannot be reached through phlogiston but is more easily reached through a living creature (a bloodgate).
If Attrahent is considered a sphere, the Inner Planes (Elements, Initiment, Introplanes) is a term describing a region that can be considered a slightly larger, encompassing sphere. This sphere of energy is accessed on higher wavelengths - thus, through the Ethereal Plane. There are six planes within the Inner Planes: Earth, Air, Fire, Water, Positive and Negative. Where these planes meet are four regions called paraelemental planes: Smoke, Ice, Ooze and Magma; and eight regions called quasielemental planes: Lightning, Steam, Radiance, Minerals, Vacuum, Salt, Ash and Dust. Illume also fuses to these Inner Planes, permitting travel from Attrahent to the Inner Planes and vice-versa.
On the other hand, the Outer Planes (Attrament, Exoplanes), while also encompassing Attrahent, is accessed on lower wavelengths - thus, through Adumbra. There are many outer planes, although they are usually divided into 17 planes: Mechanus, Arcadia, Mt. Celestia, Bytopia, Elysium, the Beastlands, Arboria, Ysgard, Limbo, Pandemonium, the Abyss, Carceri, the Grey Waste, Gehenna, Baator, Acheron and Concordant Opposition. Many of these planes have "layers" or demiplanes associated with them.

See also Persifal's Notes on Gates & Planes