Acheron (Dungeons & Dragons)

In the Dungeons & Dragons fantasy role-playing game, Acheron (/ˈætʃərən/ ACH-ər-ən), also known as The Infernal Battlefield of Acheron, is a lawful neutral/lawful evil-aligned plane of existence. It is one of a number of alignment-based Outer Planes that form part of the standard Dungeons & Dragons (D&D) cosmology, used in the Planescape, Greyhawk and some editions of the Forgotten Realms campaign settings.

The plane known as Acheron was mentioned for the first time by name in the article "Planes: The Concepts of Spatial, Temporal and Physical Relationships in D&D", in The Dragon #8, released July 1977. The plane was mentioned again in an appendix of the known planes of existence in the original (1st edition) AD&D Players Handbook, published in June 1978, where it was described as "The nether planes of Acheron of lawful evil neutrals".

Acheron is an eternal battlefield of endless conflict. It is a plane of law where conformity takes precedence over any thoughts of good. Unending battles take place across the entire plane between huge armies, with no chance of victory or cease-fire. Each layer of the plane consists of a huge number of iron cubes of varying size, from continent-sized to small islands; not all of these are actually cube-shaped, but they are generally called cubes nonetheless. The cubes float in an air-filled, infinite space, occasionally colliding with each other.

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