Secutarii Axiarchs were a type of battlefield commander used by the Mechanicum's Secutarii guard. These officers displayed perfect dedication and application to the Secutarii's art of war, but also have served on a battlefield where a fallen Titan have been successfully recovered or protected from the enemy. This is the most holy task a Secutarii can perform, and as such the Axiarch's are seen as blessed by the Omnissiah.
Once this criteria has been met, an Axiarch is remade and upgraded into a being that is inumanely stalwart and nigh-indestructible. They were typically equipped with an Arc Maul, Radium Pistol as well as Refractor Field and Titanshard Armour.