Editing Planes of Existence (section)

== The Material Plane ==
The material plane, also known as the World of Worlds, is the realm of mortals. Originally, elements from the Inner Planes were created from nothing by the creator titans to build the worlds within, but over the ages elements began to seep through the planar boundaries to be freely manipulated by titan and mortal alike.

The makeup of the Material Plane consists of several parts: Worlds, Wildspace, Celestial Spheres, and the Space Between Worlds.

=== Celestial Spheres ===
Each world in the Material Plane consists of a realm, called a terrestrial sphere or planet, encased in several crystal spheres, in which are embedded celestial objects such as suns, moons, as well as the Backdrop, or the last encasing sphere. A realm is most often land with seas, mountains, and oceans, but need not be; worlds of entirely air, vast oceans, and deep underground tunnels with seemingly no surface, have all been discovered.

Crystal spheres are nearly perfect structures, hundreds of miles thick, and seemingly transparent until one gets close enough to see the slight imperfections glittering across the surface. They are impenetrable unless using special magics or via a spelljammer ship. Spelljammers in particular are capable of warping the density of the spheres, allowing the ship to push through the crystal itself without damaging it.

==== Realmspace ====
The space within celestial spheres is known as Realmspace. Realmspace encompasses the sky above a planet all the way to the Backdrop. Within Realmspace are a variety of spheres of differing types, depending on the realm.

===== Planet =====
A planet, or realm, is the central figure of a celestial sphere, being the place where beings live. Avo is a planet and the central point of the Avonian Sphere. The edge of a planet is the point where the sky meets the Moon Sphere, or the Realm Sphere if there is no moon.

===== Moon =====
The first crystal sphere often contains a moon. It may contain a single moon, or there may be several spheres which contain numerous moons. Some worlds have no moon, but are still bound by an exterior sphere, which is called a Realm Sphere.

===== Sun =====
The second to last crystal sphere is known as the Sun Sphere and contains the sun, or multiple suns. 

===== Backdrop =====
The final, and thinnest, crystal sphere is known as the Backdrop. It is an iridescently-colored sphere dotted with the stars we see in the night sky, which are actually enormous holes in the sphere that allow light in from from the Astral Sea. At night, the Backdrop is an opaque black color, but when the sun rises, it affects the Backdrop, causing it to become transparent. The titans created the Backdrop as a reaction from their early mortal creations, who expressed annoyance at their world being continually lit, even when the sun disappeared.

==== Sphereology ====
Sphereology is a particular philosophy in [[Valwyr]], centered around the concept of the celestial spheres and trying to ascertain the “perfect” sphere. From it has arisen the '''Theory of Perfect Spheres''', which states that “a celestial sphere attains near perfection when it meets the following three criteria: it has the following spheres in this order, from inner to outer: Planet, Sky, Moon(s) (from largest to smallest), Sun, Backdrop; the Planet sphere is habitable and/or contains breathable air; and the eccentricity of these spheres’ orbits is close to 0.”