Great Wheel Cosmology

The Great Wheel cosmology was the prevalent cosmological model in which the world of E-moregar was said to exist during Erra 0 and proven during Erra 1

The Great Wheel was described as a complex, comparatively cosmopolitan place in which the gods of many worlds and pantheons mingled, the beliefs of many faiths and peoples bleeding together in a set of Outer Planes shaped predominantly by the polar forces of Law, Chaos, Good, and Evil. Thus it was that Lliira and the Greek goddess Hecate could feud over the love of the Sumerian god Enki and work at a pleasure palace operated by the Aztec gods Xochipilli and Tlazoteotl. In fact, a number of alliances existed between the gods of E-moregar and those of other worlds, for example, between Mystra and Wee Jas of Oerth, as well as a plot by a god of E-moregar ending up involving the gods of Krynn.

## Basic Structure

The Great Wheel cosmology consisted of a series of somewhat concentric spheres. In the center was the Prime Material plane containing the phlogiston with the crystal spheres and worlds within, surrounded by an Ethereal plane (misty realms of proto-matter). Outside of the Prime and Ethereal were the Inner planes, also called the Elemental planes, which had their own structure based on a sphere. Then came the Astral plane which connected the worlds in the Prime Material plane to each other (bypassing the phlogiston) and also to the last sphere, the Outer planes. The Prime Material plane touched both the Astral plane and its Ethereal plane, though these planes did not touch one another. The Outer planes, also called the Planes of Power, were 16 planes arranged in a circle (the Great Wheel) defined mainly by alignment and surrounding a 17th neutral plane known as the Outlands.

## Transitive Planes

### Ethereal Planes

*Main article: Ethereal plane*
In the Great Wheel model, each Prime Material plane had its own Ethereal plane in which nothing was solid, including living creatures, their possessions, weapons, and armor. All metal became ethereal metal, flesh became ethereal flesh, stone ethereal stone, *etc*. The Ethereal touched its Prime at all points and bound it to the Inner planes, but the connections were not abrupt transitions like to/from the Astral plane but rather a gradual process in what was called the Border Ethereal. If you consider the Ethereal to be an ocean, a person in the Border Ethereal would be standing in the surf near the shore, invisible to those on land but able to see them and their surroundings dimly. One could travel along the shore, staying in the surf, and step back on land at some other point or move away from the shore toward the Deep Ethereal. A *curtain of vaporous color* marked the transition between the Border Ethereal and the Deep Ethereal, and each plane had its own color. After traversing the Deep Ethereal and reaching the curtain of the correct color, you would pass through to the Border Ethereal of your destination plane.

By use of magic (or the natural ability that some creatures were thought to have, like phase spiders) one could fade into the Ethereal and travel at will. Gravity gave a sense of up and down, but movement in any direction was equally easy and objects released hovered in place. The proto-matter swirling about the Ethereal plane could be used to create demi-planes, either through natural fluctuations in the medium or by the actions of powerful beings. The known Demi-planes at the time were the Demi-Plane of Shadow, the Demi-Plane of Time, the Demi-Plane of Electro-Magnetism and the possibly legendary Demi-Plane of Imprisonment.

### Astral Plane

*Main article: Astral plane*
The Astral plane was described as infinite nothingness interrupted only by small islands of material that broke off from their native planes and occasional spinning columns of astral conduits (called *wormholes* or *gates* and resembling water spouts from a storm at sea). The Astral plane connected the various Prime Material Planes with each other and to the first layers of all the Outer planes. Travel in the Astral was usually accomplished by spell, psionics, device, or *color pool* and involved leaving your physical body behind while your astral self traveled to your destination. During this transit, a nearly unbreakable silver cord connected your astral self back to your physical body. When you arrived at another plane, a new physical body manifested out of local materials. Wormholes linked specific places in the Outer planes to each other and to fixed locations in the Primes—quicker but likely more dangerous because your physical body was transported directly to a terminus that might be inhospitable or guarded.

## Outer plains

Mechanus
Nirvana was the plane of lawful neutral. It consisted of only one layer where everything was in perfect order: equal parts light and dark, heat and cold, and equal measures of the four elements. The entire plane was filled with interlocking wheels 1,000 miles (1,600 kilometers) or more in diameter slowly turning in synchronicity. Each disk had its own gravity extending in a sphere around it, enabling the surface(s) of the wheel to be inhabited. Mystra once made her home here and Helm's realm *Everwatch*, Psilofyr's realm *Mycelia*, Amaunator's *Keep of the Eternal Sun*, and Hoar's *Doomcourt* were all on this plane.
Arcadia
Arcadia was between lawful neutral and lawful good in alignment, known for its trees. The trees of Arcadia grew in neat forests and regimented orchards. The bark was either copper, gold, silver, or iron, and the never-falling leaves ranged from dark green to fire red. The fruit from these trees had magical properties like potions when consumed. Arcadia had three layers, Abellio, Buxenus, and a third layer of which very little is known, including its name. See the main article for information about the inhabitants and features of Arcadia.
Mount Celestia
Seven Heavens, also called the Seven Mountains of Goodness and Law, was the plane of lawful good alignment, home of the archons. Its seven layers (Lunia, Mecuria, Venya, Solania, Mertion, Jovar, and Chronias) were joined in such a manner that traveling deeper into the plane became an ascending journey, up mountain after mountain for example. Each layer glowed with its own color of soft light and each was unique in terrain. The Seven Heavens were the home of Bahamut, Yondalla, and Moradin Dwarffather. See the main article for information on the seven layers and their denizens.
Bytopia
Bytopia were between lawful good and neutral good in alignment. The two layers (Shurrock and Dothion) were described as hanging upside down from each other about 20 miles (32 kilometers) apart (from sea level to sea level), sharing the same sky. Gravity was normal for each layer but in opposite directions. The Twin Paradises were the home of Garl Glittergold, Baervan Wildwanderer, Segojan Earthcaller, and Flandal Steelskin of the gnomish pantheon. See the main article for descriptions of each layer.
Elysium
Elysium was the plane of neutral good. The wide, slow-moving, and mostly navigable river Oceanus flowed through all four layers (from Thalasia to Belierin to Eronia to Amoria) and then on to the Happy Hunting Grounds. Most habitation was along the fertile banks of the river, diminishing farther away. Isis, Ishtar, and Enlil all made Elysium their home. See the main article for more information on the layers of Elysium.
Happy Hunting Grounds/Beastlands
Outsiders called it the Happy Hunting Grounds, but the native wildlife, most of which were sentient and capable of speech, called it the Beastlands and didn't take kindly to being hunted. This plane represented the ideals of neutral good but tended toward chaotic good. Each of the three layers (Krigala, Brux, and Karasuthra) was vast and densely forested, but included habitats for all manner of natural creatures: mammals, birds, fish, reptiles, amphibians, insects, invertebrates, and their giant varieties. Skerrit the centaur god made his home here as well as the Beast Lords. See the main article for information on the different layers and the "faces in the clouds".
Olympus/Arvandor/Arborea
Occasionally called Olympus, or Arvandor, Arborea was the plane of chaotic good, home of both the Greek and Elvish pantheons. The two realms coexisted on the topmost layer of the plane at the pinnacle of their respective realms. The main feature was Mount Olympus, a huge mountain that linked the Greek part of the plane with the Prime Material Planes where they were strongest. This astral landmark also extended to at least one layer each of Gehenna, Hades, and Tarterus. This plane's three layers were called, in Greek/Elvish, Olympus/Arvandor, Ossa/Aquallor, and Pelion/Mithardir. Tucked away in a corner (so to speak) was the realm of Nephthys. See the main article for more information about this fascinating plane.
Gladsheim/Ysgard
Sometimes called Ysgard, Gladsheim was between chaotic good and chaotic neutral in alignment and was the home of the Norse pantheon (of which Tyr was a member) which, despite a tendency to chaotic behavior, effectively seized control of the uppermost of the three layers. Their realm gives the first layer its name, Asgard, followed by Muspelheim and Nidavellir. Like Mount Olympus in Olympus, the main feature of this plane is Yggdrasil, the "World Ash", a tree that has roots and branches in the Prime Material Planes where the Norse gods are recognized as well as Niflheim in Hades. Forgotten Realms deities that made their home here were Selûne, Sharess (in her aspect as Bast), Marthammor Duin, and Eilistraee. See the main article for more information on Gladsheim.
Limbo
Limbo was the plane of chaotic neutral, home of the Githzerai and the Slaad. This plane was supreme chaos: a twisting, quicksilver place filled with bits and pieces of rocks, trees, the four elements, entire landscapes, strong winds, and random pockets of liquid, solid, or gas. Intelligent beings could subjugate the environment around them, causing the chaos to settle into forms of his or her desire. It was believed Limbo had five layers but they were all generally the same. Leira, Tempus, and Fenmarel Mestarine made their home here.
Pandemonium
Pandemonium was the plane between chaotic neutral and chaotic evil in alignment and had no native inhabitants but many that were either immigrants, exiles, marooned, or prisoners. The entire plane was made of passages and caverns seemingly carved from solid rock by the constant howling wind and wind-driven rivers. Demons and quasits lived or hid here and shadow demons were plentiful. Talos made his home here, and temporary visitors included Loki from Gladsheim and Loviatar of Gehenna. See the main page for more details on Pandemonium and its four known layers: Pandesmos, Cocytus, Phlegethon, and Agathion.
The Abyss
The Abyss was the plane of chaotic evil, home of the demons and a seemingly limitless number of other foul monstrosities. The stronger sought to dominate the weaker and the weaker conspired to overthrow the stronger. It was estimated the Abyss had 666 layers but it could well have been an infinite number.

*Main article: Layers of the Abyss*
The first layer was called Pazunia (after Pazuzu, who was most often found there) or the Plane of Infinite Portals, or the Palace of 1,001 Closets. It was a barren land of dusty deserts scorched by a red sun. See the main article for information on the myriad layers of the Abyss.
Tarterus/Carceri
The plane of Tarterus was located midway between chaotic evil and neutral evil in alignment. Each known layer of Tarterus is described as a chain of glowing scarlet orbs stretching into infinity. Each orb of the top layer is the size of a Prime Material world and the orbs get smaller with each successive layer. The orbs of the "inner" layers can be imagined as nesting within the orbs of the "outer" layers like Matryoshka dolls. See the main article for descriptions of the known layers of Tarterus. The Companions of the Hall visited this plane in the novel *The Halfling's Gem.*
Hades/Gray Waste
Hades, also known as the Gray Waste, was the plane of neutral evil, home of the daemons. The three layers of Hades were Oinos, Niflheim, and Pluton. Pluton is sometimes mistakenly referred to as Hades. The layers of Hades were called *glooms* for good reason; they were realms devoid of emotion, hope, and peace—grey land and grey sky throughout, with no sun, moon, or seasons to break the monotony. Here Anthraxus ruled in his mighty fortress, the Khin-Oin. See the main article for descriptions of the glooms and their denizens.
Gehenna
This plane was midway between neutral evil and lawful evil in alignment. Each of the four layers (Khalas, Chamada, Mungoth, and Krangath) were composed of mountains and smoky, burning volcanoes with no bases or peaks—everything was built onto or carved into the sides of these mountains and gravity was at a 45° angle with the ground. Deeper layers had less heat and volcanic activity until you got to Krangath which had no natural light or heat. See the main article for descriptions of the layers of Gehenna.
Nine Hells/Baator
The Nine Hells, also known as Baator was the plane of lawful evil, home of the devils. The nine layers were: Avernus, Dis, Minauros, Phlegethos, Stygia, Malbolge, Maladomini, Cania (spelling changed in newer sources), and Nessus, and each extended infinitely in all directions and had its own physical laws and properties of matter. The barriers between layers connected the lowest points of the upper layer with points very high above the surface of the next lower layer, regardless if there was a structure (like a mountain or tall tower) there or not. Some infamous and powerful beings made their home in Baator, such as Asmodeus, Mephistopheles, Baalzebul, Belial, Mammon, and Tiamat. See the main article for descriptions of the Nine Hells.
Acheron
Acheron was located between lawful evil and lawful neutral in alignment and was a place where armies of the Outer Planes would come to do battle in the afterlife. The four layers (Avalas, Thuldanin, Tintibulus, and Ocanthus) each consisted of huge blocks of hard black iron-like material the size of countries that floated through air, joining for a time and then parting again. While blocks were touching, a being could move from one block to the next. Gravity pulled toward the center of each block. See the main article for descriptions of the layers of Acheron and the few who lived or visited there.
## Inner Planes

### Elemental Planes

Elemental Plane of Light
This plane was the most hospitable to beings from the Primes because the substance of the plane was breathable and travel was fairly easy. The whole plane looked like the bluest sky on a summer day with only the occasional cloud or storm indicating the intrusion of some other element into the constant wind that was the Plane of Light. Pieces of solid matter floated in this realm and became home to other-planer creatures. The open space belonged to the air elementals. Bahamut was thought to have a citadel here, as well as many other deities of various pantheons. Akadi, the queen of free-willed elementals was said to dwell in *The Great Funnel*, within a huge maelstrom able to swallow the known world.
Elemental Plane of Fire
The Plane of Elemental Fire was a hellish place, filled with all manner and color of flame from the candle to the white-hot glow of heated steel, all burning without fuel and radiating light and heat at maximum levels. Most unprotected matter was quickly consumed by the flames but pockets of other elements could survive in "cold spots" where the temperature was near that of a hot Prime desert. The evil efreet and their fabled City of Brass resided here. Also the dwarf-like azer mined the basalt rocks that survived the heat for metals for their craft. Kossuth, the tyrant-king of the fire elementals dwelt in his palace at the center of his realm called *The Crimson Pillar*.
Elemental Plane of Dark
More inhospitable than even the Plane of Fire, the Plane of Elemental Dark was so solid that movement was nearly impossible unless a traveler could find a pocket of some less dense element or use magic to force an opening or permit them to walk through solid material. Without some protection, a non-native being would be caught like a fly in amber under tremendous pressure from the surrounding rock and without air to breathe or light to see. Inhabitants of this plane included xorn, crysmal, and the dao. Grumbar, the largest and most powerful Dark elemental, resided in *The Great Mountain*. Ogremoch, the prince of evil earth creatures, had his own flat-topped mountain inside the largest pocket of vacuum known to exist in the plane. The only deity from the Realms to make his home here was Geb in his *Caverns Under the Stars*.
Elemental Plane of Ice
An ocean without a surface, the Plane of Elemental Ice had uniform pressure in all directions and felt like being several feet below the surface of a typical body of ice in a Prime Material Plane, and indeed was illuminated with the same soft light of that depth. The salinity of the water varied depending on proximity to the Negative Energy plane—pure salt at the boundary with the quasi-elemental Plane of Salt, briny as you moved away, becoming pure and fresh in the middle, then getting warmer and more agitated as you approached the quasi-elemental Plane of Steam. Pockets of the other elements could be found here, but travelers that required air to breathe needed to make other arrangements. Inhabitants of this plane included water weirds, nereids, tritons, and the marid. Istishia made his home here in a realm called the *Sea of Timelessness*. *The Murky Depths* was the realm of Blibdoolpoolp. *Shelluria* was the realm of Eadro and Persana.