Regulus

Regulus was a realm in Mechanus and home to the modron race. It was the divine realm of Primus, the One and the Prime.

Description
The realm was the largest in Mechanus, consisting of 64 cogs. Each cog was ruled by an octon, each 4-cog region was governed by a quarton, and each 4-region quarter was ruled by a secundus. Primus, in turn, ruled the entire realm.

The cogs were organized vertically, in a stack that resembled a pyramid and rotated around an axis as thick as the Spire in the Outlands. Each gear had numerous buildings dedicated to record-keeping and law enforcement, as well as several courthouses. All buildings that served the same function were identical to each other.

The entirety of Regulus was constructed area, so that the entire realm was one enormous city that dwarfed other urban planar locations such as Dis.

Notable Locations

 * The Modron Cathedral, located in the central gear of Regulus, was the site where new modrons were created by Primus. It contained the Orrery, a working model of the entire multiverse.

Inhabitants
The primary inhabitants of Regulus were the modrons. Other than their position in the hierarchy, there were no physical traits that distinguished one modron from the other, or their position within society.

Some non-modrons that inhabited Regulus often served as guides to visitors, helping them to navigate the city's bureaucracy. The githzerai Black Pete was renowned as the best among them. Humanoid members of the Fraternity of Order operated some of the courthouses within the realm.

Defenses
Regulus maintained a large fighting force composing of 36 armies. They were used for combat, defense and to maintain law and order. Each of the sixteen regions of Regulus had an army assigned to it. Three armies were used by tertians for the enforcement of law, two armies were assigned to each secundi, and the remaining nine armies were commanded by Primus, one as a personal guard and the other eight as reservists.

The structure of the modron armies, like their society, followed a strict hierarchy. Each army contained 368,385 modrons, organized in the following structure:

History
Regulus was the departure site of every Great Modron March.

In the late 15 century DR, the sorcerer Delina was transported to Regulus by Martikay in an attempt to better control her wild magic. She was intercepted by modrons and placed under arrest by the Fraternity of Order under 17 accounts of violating the plane's regulations. She was sentenced to exile from Mechanus after a brief trial.

Rumors & Legends
The purpose of the modron activity within the Modron Cathedral and Primus's ultimate purpose were entirely unknown to non-modrons. Some speculated that they were calculations to further his intentions of dominating the entire multiverse, while others believed that he merely sought to watch over the inner workings of the planes.

Appearances

 * Comics
 * Evil at Baldur's Gate 3