Mechanus

In the Dungeons & Dragons fantasy roleplaying game, Mechanus, also known as The Clockwork Nirvana of Mechanus (or simply Nirvana in AD&D 1st Edition) is a purely lawful 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 Greyhawk, Planescape and some editions of the Forgotten Realms campaign settings.

It is the plane of ultimate law and order (neutral or chaotic creatures take -2 penalty on Charisma, Intelligence and Wisdom-based checks), where the souls of people of lawful neutral alignment go after death. Mechanus operates on a strict schedule where every action is planned, measured and controlled perfectly. It is home to the construct-like geometric modrons, the law-enforcing inevitables and the regimented giant ants called formians.

The plane known as Nirvana 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 the "plane of ultimate Law". 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 "Nirvana of absolute (neutral) lawfuls".

Mechanus consists of a single infinite plane; there are no constituent layers. Mechanus shares its borders with the neighbouring planes of the Peaceable Kingdoms of Arcadia and the Infernal Battlefield of Acheron; travel is possible between Mechanus and these planes at certain locations.

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