This will be another long, rambling post to get my thoughts out. I’ll try to keep it in order, but it may end up confusing anyway.
Aerinwohl is the name of the planet, not the Campaign Setting. I’ll figure out a name for the setting eventually though. Aerinwohl circles a single, yellow sun and the planet is about the size of Earth. It used to have a single moon, but that was destroyed when Illshanafiir sacrificed himself to end the Incursion. The planet now has a ring of debris that is made up of the remnants of the moon. There are other planets in the system, but I haven’t thought about them. I’m going to assume that they are unreachable and uninhabited.
The planet has four definitive continents. One sits at the bottom of the planet, covered in ice and glaciers. One sits in the southern hemisphere and is the home of the V’reen. North east of that continent is a large one that is home to Magachiro, but mostly uncharted. The main continent resides in the northern hemisphere and is home to the majority of intelligent species and contains the location where the Incursion started, as well as Eberdeen and Bisgemalkin. That continent is where most of the detail in later posts will be hosted.
All of this only details the Material Plane, where physical things live and die. Cosmology, on the other hand, is something else entirely. The planet sits in a star system inside a galaxy, which is inside a universe. This could be our universe, or something else entirely. Since the people of Aerinwohl do not have space travel, it doesn’t really matter.
Planar Cosmology is a wholly different bag. The planes are not physical places that can be traveled to, they are wholly different universes that are linked to the physical universe. By sidestepping into another plane, people can move great distances, summon creatures from those planes, or pull forth energies to create attacks or protection. At one point, Aerinwohl was connected to these other planes. The Outer Planes for a great set of different environments, most tied to a specific alignment and the creatures that live there the embodiment of that alignment in totality. Deities also live on these planes and many of them have complete control over the physical and metaphysical aspects of the plane.
However, that all changed. To end the Incursion, Illshanafiir destroyed the moon, forced the devils back to their home plane, and severed the connection between the system Aerinwohl exists in and the Outer Planes. There were gods on both sides of the new barrier, but those on the outside of it could no longer see it. They could no longer empower their worshippers, and their worshippers could no longer seek them for guidance. This was the beginning of the new world when many clerics sought to reconnect with their god, others tried to find new ways to gain spells, and the New Gods left on the planet spent resources to create a new source of divine energy.
Most of the new power sources came from either the Luminance or the Shadow. These planes parallel and overlap the Material, but are twisted versions of them. Luminance is bright and overladen with life in its purest forms. There are some creatures of good still there, and creatures who create life and empower it are prolific. In contrast, the Shadow is a dark, gloomy world of death and undeath where the undead gain their new unlife from. It is also evil aligned, so most spells that harm the soul are powered from it.
The exact makeup or position of the barrier is hard to define. It does not exist as a physical wall around the planet, but instead as a metaphysical wall between dimensions. It cannot be seen or measured, but it still exists. The barrier is strongest between the Material and Outer alignment-attuned planes, but it also exists between the Material and Inner elemental planes. It is weaker here, however, and the New Gods were able to breach the barrier to the planes ever so slightly and still retain some of their power. While most of them reside in the Luminance, Shadow, or Material planes, a few reside in the various Elemental Planes and nearly all of them have some conduit to the Elements to give spells to their clerics.
There are also clerics dedicated to single element. They fuel their spells with the power of their chosen element, but do not understand that they have made a pact with an agent of that element. When they were initiated, they made contact with that element and communed with some being of the plane, but who actually gives them their power or how it works is beyond mortal thinking.
There also exists the Place Beyond the Stars. The Mad God Tiddlestin left her home in the Outer Planes to help teh gnomes and halflings with their battle during the Incursion. When the last gnome was killed by Mythkael, she went insane and caused madness in the remaining halflings. Her thoughts now destroyed, chaotic, and unimaginable, she fled to the Place Beyond the Stars and has resided there ever since. What she does there is unknown, but Chaos Priests that worship her still receive spells from her, though now most of her clerics go insane eventually and have a limited range of spells compared to others.
Finally, there is the place where the Collective exists. The collective only serves to strengthen the barrier. What was once a mass of swirling soles in the ether has coalesced into a sentient being of godlike power and alien thinking. The Collective is always growing as more souls are absorbed into it, while the oldest and weaker souls are eventually so consumed by the Collective that they cease to exist as anything but fuel.
There are also a few demiplanes that intersect with the Material Plane. Jho’Shikkur has his Celestial Temple (need a new name for that). Mythkael has his temple-fortress deep in the Night Below where he acts as both king and god to the drow. Selaine is usually resting deep under the waves in a place where the seas join with the elemental Plane of Water. Since she had always been associated with seas and water, she maintained her connection to the inner plane and has had relatively few changes in her worship. Rurik, the half-dwarf/half-human demigod maintains a demiplane like Jho’shikkur, but his is a great library of all the secrets and contract bonds of the world. He is the keeper of knowledge, secrets, and profit, and those who swear an oath on the Library of Rurik, do so knowing that breaking that contract is worse than death. The last deity is the Horde Father Gulgac who also resides on a demiplane he created for himself called the Colosseum, where the dead orcs come to fight for eternity. It is rare for an orc soul to join the Collective unless they have turned their back on their people.
And that, folks, is the planar cosmology of the Yet-To-Be-Named campaign setting centered on the planet Aerinwohl.