Legio Cybernetica

The Legio Cybernetica is one of the oldest sub-branches of the Adeptus Mechanicus. They can trace their lineage to the birth of the Imperium of Man and, it's assumed, to the times before its founding. Its members regard themselves as an elite, as their Legio has a long storied history of serving the will of the Emperor of Mankind. This was not always the case as many of those within the Legio broke faith with the Emperor during the Schism of Mars, siding with the traitorous forces of the Warmaster Horus and fighting alongside his forces throughout the Horus Heresy. When this conflict ended those dishonoured Cohorts of the Legio fled into the Eye of Terror, where they remain to this day. The Legio Cybernetica pledged itself anew to the Imperium -- its members taking binding oaths of loyalty more terrible than any Astartes Chapter oaths. Over the millennia they have regained the respect and admiration of the rest of the Adeptus Mechanicus as well as the other myriad organisations of the Imperium.

Great Crusade
Being one of the most ancient factions of the Adeptus Mechanicus, the Legio Cybernetica can trace it's history to the bygone era of the 31st Millennium during the Great Crusade. Many of their robot cohorts fought alongside the Astartes Legions in the compliance of hundreds of newly rediscovered worlds. They were instrumental in helping to bring back untold numbers of these human-settled worlds under the control of a single human authority, ending the isolation that had consumed the human-settled galaxy during the long years of the Age of Strife. This massive expansion of the Imperium continued unabated until the Emperor's realm encompassed nearly the entire galaxy.

But soon, a new and unexpected threat emerged to challenge Mankind's dominance over the galaxy. A galaxy-wide interstellar revolt was instigated and led by the Warmaster Horus, greatest and most beloved of the Emperor's super-human, genetically-engineered sons, the Primarchs. But even before the opening stages of his planned insurrection began, he knew he would have to secure the support of the Adeptus Mechanicus and their superior technology and weapons if he was to defeat the Emperor and conquer the galaxy.

Schism of Mars
In order to win over the loyalty of many of the Adeptus Mechanicus, Horus promised he would give them the lost secrets of ancient Standard Template Construct (STC) technology that had been recovered from the worlds of the recently subjugated Auretian Technocracy by his own Sons of Horus Legion. Convincing the Fabricator-General Kelbor-Hal of his resolve, the Warmaster secured the traitorous Arch-Magos's support by promising increased autonomy for the Mechanicus against the autocratic rule of the False Emperor. As a gesture of gratitude for his continued support, Horus supplied the Fabricator-General with vital information to open the sealed Vaults of Moravec -- a repository of forbidden technology and innumerable artefacts corrupted by the malign influence of Chaos. The Emperor had ordered this repository sealed two centuries earlier. Their dark bargain struck, the Fabricator-General pledged his continued support for the Warmaster, assisting the Traitors with all the technology at their disposal.

Soon civil war erupted across the Red Planet, as the tense relations between the various Mechanicus Magi who governed Mars erupted overnight into open civil war. When the Fabricator-General and his Dark Mechanicus forces moved against the Loyalist factions, the Robot Cohorts under the command of the Legio Cybernetica willingly obeyed their traitorous masters. In the subsequent fighting many more of the Adeptus Mechanicus soon joined the Horus and his Traitors, not bothering to alter the fact that parts of the Legio had been the first to declare for the Warmaster. Following the defeat of Horus at the hands of the Emperor, and the banishment of the Traitor Legions to the Eye of Terror, those within the Legio Cybernetica whom had sided with the Traitors fled in disgrace as well. There they have remained for the last ten millennia.

Organisation
The Legio Cybernetica specialises in only one of the myriad areas of technical arcana, primarily the care and construction of all Imperial Robots throughout the Imperium. Once employed by the forces of the Imperial Army and the Space Marine Legions they are now exclusively used by the Legio. In their heyday, the Legio Cybernetica was organised into several thousand Cohorts, although only a small percentage of these were ever active at any given time. Each of these Robot Cohorts were in turn organised into Maniples of 3, 4 or 5 Robots plus a Legio tech-adept. Numbering rarely more than 100, the number of Maniples within a Cohort could greatly vary. However, a Cohort was usually spread across an entire Astartes force of several Chapters or a single large Imperial Army force. The use of more than 4 or 5 Maniples in a battle were rare, but not unknown. During the Horus Heresy, particularly large numbers of Robots were committed by both the Loyalists and Traitors in an effort to minimise human casualties until a decisive final battle could be fought. In addition, the organisation was further divided into a number of sects.

Each of these Maniples were virtually a self-contained unit, with a single tech-adept typically overseeing the management of four units on the battlefield. They were responsible for little more than to give the Robots their final 'wetware' programs and then monitor their progress. However, they were also charged with the equally vital task of monitoring the progress of their Maniple, and to ensure that a damaged Robot was destroyed as quickly as possible, to avoid any possible danger to their own side. This was done by remotely activating the Robot's self-destruct system. There were also a number of other, lesser tech-adepts who performed all maintenance and repair functions for the Maniple (though their presence on the battlefield was rare). Possessing the ability to repair virtually any item of Imperial equipment, it was said these tech-adepts of the Legio were worth their weight in spares.

Members of the Legio Cybernetica tend to eschew the gross cyborg augmentations of their colleagues within the Mechanicum in favour of subtle enhancements that do not disfigure or dilute their outwardly human aspect; but those who know a member of the Legio know that whatever humanity they do show is rare and fleeting. Those senior rank or equally high status are known to wear the circuit-laced robes of a Mech-Lord to identify their esteemed status. These senior Legio members are usually accompanied by a small unit Maniple of Robots for their personal protection.