Baator

In the Dungeons & Dragons fantasy role-playing game, Baator, also known as the Nine Hells of Baator or the Nine Hells, is a 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. It also exists as one of a number of faith-based Outer Planes that form part of the separate 3rd-Edition Forgotten Realms cosmology, used in the setting of the same name.

Baator is stylised as a plane of sinister evil and cruelty. The different types of devils that dwell here obey a strict hierarchical caste-like social structure. Each continually plots to advance their position through treachery and deception. Unlike the demons of the Abyss, the devils are highly organized, with a logical and calculating nature.

The plane itself is composed of nine different layers, each of which models a differing but no less inhospitable and dreadful environment, including barren plains of ash and rock to frozen wastes of endless ice.

The plane known as the Nine Hells 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. In the article Gary Gygax describes the plane as one of the "Typical lower planes". 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 Nine Hells of absolute lawful evil".

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