Plane (Dungeons & Dragons)

The planes of the Dungeons & Dragons roleplaying game constitute the multiverse in which the game takes place.

In the earliest versions of Dungeons & Dragons, the concept of the Inner, Ethereal, Prime Material, Astral, and Outer Planes was introduced; at the time there were only four Inner Planes and no set number of Outer Planes. This later evolved into the Great Wheel cosmology. The fourth edition of the game used a different, very simplified cosmology with just six main planes called the World Axis Cosmology. The fifth edition has brought back a new version of the Great Wheel cosmology.

In addition, some Dungeons & Dragons settings have cosmologies that are very different from the "standard" ones discussed here. For example, the Eberron setting has only seventeen planes in total, most of which are unique to Eberron.

This standardized layout of the planes was presented for the first time in Volume 1, Number 8 of The Dragon, released July 1977. The known planes of existence were presented again in an appendix in the original (1st edition) AD&D Players Handbook, published in June 1978. The planes were expanded upon in the original Manual of the Planes, released in 1987. It was the core cosmology in both editions of AD&D and the 3rd and 3.5 editions of D&D. 5th edition reintroduced a modified version of the Great Wheel.

Many Outer Planes were renamed in Advanced Dungeons & Dragons Second Edition in the Planescape campaign setting, released in 1994. In the Third Edition Manual of the Planes, published in 2001, the old and new names were combined together, the Demiplane of Shadow was promoted to the Plane of Shadow, the Prime Material Plane was shortened to the Material Plane, and it was stated that each Material Plane is connected to its own unique Ethereal Plane.

The cosmology is usually presented as a series of concentric circles, with alternating spatial and transitive planes; from the center outwards, they are ordered as follows: Inner, Ethereal, Material, Astral, Outer Planes, and the Far Realm. The Shadow Plane and the Dimension of Time, if they are included, are separate from the others, and usually represented as being connected to the Material Plane. Demiplanes, although most commonly connected to the Ethereal Plane, can be found attached to any plane. All planes, save the demiplanes, are infinite in extent.

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