The Ethereal Plane is often likened to an ocean, but rather than water it is a sea of boundless possibility. It consists of two parts: the Border Ethereal which connects to the Inner and Prime Material planes, and the Deep Ethereal plane which acts as the incubator to many potential demiplanes. From a Border Ethereal plane a traveler can see a misty greyscale version of the plane from which they are traveling; however, each plane is only connected to its own Border Ethereal, which means inter-planar travel necessitates entering the Deep Ethereal and then exiting into the destination plane's own Border Ethereal plane. Many demiplanes can be found in the Deep Ethereal plane; most demiplanes are born here, and many fade back into nothingness here.
The Ethereal Plane, also called the "Ether", entirely surrounds the Prime Plane and the four Elemental Planes. The Ethereal Plane is 'coexistent' and 'coterminous' with these planes, meaning that every point on the Prime Plane and on the Elemental Planes touches a point on the Ethereal, although there are areas of the Ethereal that do not border the Prime or the Elemental Planes. These coexistent regions of other planes are visible from the Ethereal Plane, but it appears muted and indistinct, its colors blurring into each other and its edges turning fuzzy. The Material Plane itself is visible from the Ethereal Plane, but it appears muted and indistinct, its colors blurring into each other and its edges turning fuzzy.
While it is possible to see into the Material Plane from the Ethereal Plane, the Ethereal Plane is usually invisible to those on the Material Plane. Normally, creatures on the Ethereal Plane cannot attack creatures on the Material Plane, and vice versa. A traveler on the Ethereal Plane is invisible, incorporeal, and utterly silent to someone on the Material Plane.
The Ethereal Plane is mostly empty of structures and impediments. However, the plane has its own inhabitants. Some of these are other ethereal travelers, but the ghosts found here pose a particular peril to those who walk the fog.
- No gravity.
- Infinite size. The Ethereal is always infinite or finite depending on the plane or planes it is adjacent to. As the Mystaran Ethereal is always adjacent to an infinite plane, it is technically also infinite.
- Alterable morphic. The plane contains little to alter, however.
- No Elemental or Energy Traits (specific locations may have these traits, however)
- Mildly neutral-aligned.
- Normal magic. Spells function normally on the Ethereal Plane, though they do not cross into the Material Plane.
- No Sphere Bias Traits (specific locations may have these traits, however)
The only exceptions are spells and spell-like abilities that have the force descriptor and abjuration spells that affect ethereal beings. Spellcasters on the Material Plane must have some way to detect foes on the Ethereal Plane before targeting them with force-based spells, of course. While it’s possible to hit ethereal enemies with a force spell cast on the Material Plane, the reverse isn’t possible. No magical attacks cross from the Ethereal Plane to the Material Plane, including force attacks.
The mists of possibility translate into a nourishing gas appropriate to those who breathe it; thus, both air-breathers and water-breathers can equally survive on the Ethereal Plane.
Taste, touch, and smell are somewhat muted on the Ethereal Plane, though hearing is sharpened in the thick, possibility-laden medium of the plane.
Protomatter is a semi-solid or solid substance, generally white with bluish tinges. The most ephemeral form, known as ephemeral protomatter, forms with any sufficiently strong movement, and dissolves just as quickly. Very rarely, ephemeral protomatter may become a more stable type of protomatter known as quintessential protomatter or quintessential ether. The web of a phase spider is made of quintessential ether, and this forms one of the components of a portable hole. Very rarely, or in the case of very rare phase spiders, quintessential protomatter may become stable protomatter, which lasts indefinitely and slowly accumulates. It is believed that if enough stable ether accumulates in one place, a new demiplane will be created.
Larger fluctuations, such as those caused by the flexing of curtains of vaporous color, by ether cyclones, by the vortices that connect the elemental planes with the Prime Material, are much more likely to create more stable forms of protomatter.
Naturally occurring streams and falls also exist in the Deep Ethereal, constantly forming rivers of ephemeral protomatter steaming into the mists.
Each plane that borders the Ethereal Plane (except for a few demiplanes) has a Border Ethereal region. From the vantage of the Border Ethereal, one can perceive the Border Ethereal and the plane it touches simultaneously. The adjoining plane is reduced to shades of gray, and seems to be shrouded in fog. Sound on the adjoining plane is muffled and hard to make out clearly. Those on the Border Ethereal are invisible and inaudible to those on the adjoining plane except through magic, and cannot communicate across the planar divide without magic.
Creatures on the Border Ethereal are aware of the adjoining plane's gravity but not bound by it; they can move into the sky or into the earth by an act of will. Certain substances will block ethereal travel, for example lead, gold, diamond, expensive crystal, stone mortared with the blood of a gorgon, and all living creatures (including, for example, walls covered with crawling ivy). Ethereal travelers must move around these obstacles. Null-magic areas and dispel magic effects cause ethereal travelers to fall back into the adjoining plane.
By another act of will, border ethereal travelers may move into the Deep Ethereal, passing through the Wall of Color on the way.
This part of the Ethereal Plane exists independently, an infinite sea of mist without gravity or parallel planes to provide a traveler with a sense of direction. Shimmering curtains of differing colors help identify passages to the Border Ethereal; the exact color of the curtain can help identify which plane the region borders.
Movement is accomplished by acts of will, the mind translating the possibility of the plane into movement. Faster movement is possible by sacrificing physical substance, with increasing damage of a traveler's corporeal form providing increasingly fast movement.
- Ether cyclones are spiraling storms (resulting from the friction between the various planes of existence) that suck up all in their path, throwing them off course or into another plane.
- Ether gaps are catastrophic collapses in possibility, the legacy of destroyed timelines and the like, that pull all who come too close outside the multiverse entirely, to be forever lost. They first manifest as a strange tugging in the mist, the current growing stronger the closer a traveler approaches until they become unstoppable, spiraling holes of death in the substance of reality. One ether gap, known as Leicester's Gap, leads to the Far Realm. Others are known to lead to aborted timelines that never came to pass.
- Vortex fronts. Vortices like endless cyclones connect the Elemental Planes and the Prime Material Plane, channeling elemental material from one plane to another. For example, a vortex to the Elemental Plane of Water may connect to a point deep beneath the Ocean, or a vortex to the Quasielemental Plane of Ash may touch a desert. Vortices may also connect one Elemental Plane to another, providing a shortcut between, for example, the Elemental Plane of Earth and the Elemental Plane of Fire (one such vortex, known as the Iron Crucible, exists near the City of Brass). From the Ethereal Plane, these vortices resemble endless shadowy tubes. They may, at irregular intervals, burst with elemental material and pulse with dangerous wave fronts made of temporarily compressed ether. These "vortex fronts" can be used as propulsion by those who know how to "ride" them in the same way a surfer rides a wave.
Curtain of Vaporous ColorEdit
As mentioned above, these shimmering curtains help identify which plane the Border Ethereal region beyond will touch. For example, red curtains generally lead to the Elemental Plane of Fire.
The Curtain of Vaporous Color is also the Region of Dreams, the realm in which the dreams of creatures on the adjoining planes take place. Reality is somewhat thinner and more tenuous in the Region of Dreams, capable of fitting into the thin curtains without the dreamers noticing. Occasionally, however, dreamscapes will escape the Region of Dreams and enter the Deep Ethereal, taking on substance and increased reality from the mists. Some manage to sustain themselves in this way indefinitely, becoming semi-permanent demiplanes spun from ethereal mist and dream.
Ethereal Curtains, exist in the Ethereal Plane but an Outer Plane must allow access from the Astral for it to have a corresponding curtain since curtains usually create conduits through the Astral.
Very rarely a curtain may be found that leads to the Shadow Plane and 5% of these curtains actually form a conduit through the Deep Shadow and to the Negative Energy Plane.
- Tweens are amorphous energy beings that affect the luck of those they attach themselves to.
- Rabbiun are serpentine beings who fly like spears through the Deep Ethereal.
- Chronolilies are flowers that subsist on the temporal currents originating - some say - in the Demiplane of Time. Nearly 50 feet in diameter, the pools of nectar in their blossoms can reveal images of the past, present, or future.
- The nathri are 4-foot-tall humanoids with dark greenish skin and long, unruly black hair. They are fierce, wild barbarians who conduct lightning-fast raids on demiplanes before retreating back to their homes in the Deep Ethereal. They are on the lower end of the food chain for beings like magran and xill.
- Red-skinned, four-armed aliens, the xill are an aggressive race from the Ethereal Plane, feared and despised by most natives of planes bordering the Ethereal. Their origins are unknown, but they speak the language of the baatezu. The modern xill race is divided into two distinct castes: the High Clans – the so-called Settlers, and the Low Clans – the Hunters. The Low Clans are savages who disdain the use of tools, but the High Clans are civilized sophisticates with an equal disdain for their cousins' primitive ways. Both races of xill worship a god called Sixin.
- The gingwatzim are beings of raw life force created by the last Emir of Castan. There are six different species of varying powers, but all resemble glowing spheres of swirling, sparkling gases. They can also be bound inside living creatures or inanimate objects. On their home plane, the more powerful types prey on the less powerful ones.