Among the many factions of the Mechanicus Calixis are those adepts who believe that the fracturing of the Lathe Worlds has grown out of hand. They look upon the petty bickering, empire building, and general discord sown throughout the Sector as a waste of precious resources that could be better served going to any of a number of more legitimate causes, most often their own. A loose confederation of like-minded adepts rather than a formal faction, the Magos Fidelis nevertheless hold considerable power, as quite often the merest threat of intervention from Mars is enough to cause a wayward adept to back down.
The adepts of the Magos Fidelis are among the most conservative and traditional members of the Mechanicus. Faithful followers of the Omnissiah, often characterized as excessively orthodox within the Cult Mechanicus, most of the tech-adepts and lesser Lathesmasters nevertheless afford them great respect for their dedication and the force of their belief. The most fervent members of the Magos Fidelis believe that a more firm hand, directly from Mars, is needed to set the Lathe Worlds to rights, although at present all petitions for direct intervention have not garnered any response.