Planes
This Campaign Setting takes place entirely within the scope of a cosmogony that greatly resembles an hourgless.
Hourglass Cosmogony¶
In the worlds of fantasy roleplaying games, the planes are otherworldly dimensions filled with adventure, magic, danger, and world shaking conflicts. To travel to a plane usually requires a portal or artifact that can take you there or a magic spell like 'Plane Shift'. The material component for the spell 'Plane Shift' is a tuning fork attuned to the plane you're travelling to, a prized and rare magical treasure in much of this campaign setting.
The Hourglass Cosmogony takes the approximate shape of an hourglass or, to be specific geometrically, a bicone. It is composed of two cones that are aligned, pointing in opposite directions, and intersecting at their apexes, where the Material Plane and Prime Cluster are found.
Imagine it this way: there is an upwards, a downwards, a northwards, a southwards, an eastwards, and a westwards. There are two more directions, besides these six, in which the two cones spread out, leading to the other planes. These two other directions are, academically speaking, referred to as inwards and outwards. Travelling inwards broadly takes you in the direction of the first cone and travelling outwards broadly brings you to the second.
The first cone is composed of the planes concerning the material world. They're composed of energy, matter, and life force. This includes the Ethereal Plane and Inner Planes. Beyond the Inner Planes sits the Primal Chaos.
The second cone is composed of the planes concerning the metaphysical spirit. This includes the Astral Plane and Outer Planes. Beyond the Outer Planes is the Void Chaos.
Together, the Astral Plane and Ethereal Plane are known as the Transitive Planes because, in order to travel to the Outer Planes and Inner Planes, you must travel through the respective Transitive Plane. Similarly, the Primal Chaos and Void Chaos are collectively called the Realms Beyond. Either are far too dangerous for any mortal creature to approach. Even the Deities don't dare.
Besides these broad categories, there are also the Demiplanes, which are smaller, definitively finite planes. These usually occur as pockets of reality within other larger planes. Sometimes, they appear infinite, but lead to other planes. Sometimes, they're enclosed with portals or spells required to travel to other planes.
The specific nature of each plane can be remarkable. Although the planes share many characteristics, many physical laws and magics are different on different planes. One example of this is how planes intersect. Planes that are adjacent to one another can be either coterminous or coexistent.
Coterminous planes are planes that meet at specific locations. For example, you can travel to Heaven from Eden. One can be seen from the other and walking between the borders of the two is just like walking past the borders of a city.
Other adjacent planes coexist in the same space with one another, overlapping and blending a little into one another. For example, Silhouette is always visible from the Material Plane. Shadows which come from Silhouette are projected by every lit object in the Material Plane and some creatures from that plane can pass bodily through into ours at any location and at will. It usually takes magic or a special ability to move between coexistent planes but, in some cases, it's possible to pass between the two worlds either through willing it or through specific movements. In general, it's more akin to not knowing how to move our bodies across the planar threshold than it just not being possible for our bodies to do so.
