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.
Throughout Mechanus exists a series of interlocking cogs that float in space, intersecting at all angles and directions. Many of the cogs are gigantic, stretching many miles across and turn so slowly that the rotation is undetectable. Smaller cogs can move at much higher speeds, but no acceleration is experienced, except at the very edges. Usually smaller cogs bunch up with larger ones; these are called knots. The gears are fiercely guarded by gear spirits that reside within them. The gravitational force is oriented towards the face of each individual cog, making intercog travel a disconcerting experience for the uninitiated.
Regulus is the home of the construct-like Modrons. Their strict hierarchy originates from Primus, a greater deity, which resides here. Regulus consists of a total of sixty-four cogs, a number that never varies. It is divided into four quarters of sixteen cogs, each ruled by a Secundus. Each quarter is in turn split into four regions, of four cogs, each ruled by a Quarton. Finally, the regions are further subdivided into four sectors, of a single cog each, ruled by an Octon.
At the center of the Formian realm lies a central cog more than three-thousand miles across, where the Scion Queen Mother, leader of the Formians resides. The central cog supposedly imparts the movement to all other cogs in Mechanus.
Anu is ruled by Anu. Here exists a single huge disc, upon which his palace rests.
The Jade Palace is home to Shang-ti, the Celestial Emperor. His palace is the focal point of the Celestial Bureaucracy, which also supervises the Chinese pantheon. The Great Library can be found here.
Possibly named after John von Neumann, it is a series of mysterious self-sustaining factories that produce Inevitables. It is managed and presided by the Hub of Elders, who seeks out any non-lawful activity (broken contracts, etc.) that needs to be corrected.
The plane of Mechanus is the location of a number of godly realms, including the god Pholtus' realm of The Path of Law, Helm's realm of Everwatch, the myconid deity Psilofyr's realm of Mycelia, Nai No Kami's realm of The Shaking Land, Yama's realm of Yamasadena, Rudra's realm of Focus of Energy, and Varuna's realm of The Vigilant Eye.Axial dragon
Visilight - Also known as Parai
Mechanus was originally named after the Buddhist concept of Nirvana, which could be described as a perfectly ordered balance between extremes. Since it was detailed in the 1st edition Manual of the Planes (1987), however, it has changed markedly from this concept. It was renamed "Mechanus" in the Planescape Campaign Setting (1994).Grubb, Jeff. Manual of the Planes (TSR, 1987).
Grubb, Jeff, Bruce R Cordell, and David Noonan. Manual of the Planes (Wizards of the Coast, 2001) ISBN 0-7869-1850-0.