Plane (Dungeons & Dragons)

In the standard cosmology of the Dungeons & Dragons roleplaying game, the planes of existence are alternate dimensions. They can be grouped into five basic categories: the Inner Planes (places of raw matter and energy); the Outer Planes (places of gods, souls, and raw philosophy and belief); the Material Planes (worlds balanced between the philosophical forces of the Outer Planes and the physical forces of the Inner Planes, these are the standard worlds of fantasy RPG campaigns); the transitive planes (connecting the other planes and generally containing little, if any, solid matter or native life); and the demiplanes (minor, often artificial planes, often possessing qualities of the other four types of planes).
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