The Imperium has numerous means of making war upon its numerous enemies, from the relentless assault of countless thousands of Imperial Guardsmen to raining virus bombs upon them from orbit. The very subtlest, however, and one only unleashed upon the express word of the High Lords themselves, is the Officio Assassinorum. This secretive order trains and deploys the most deadly assassins alive, each a member of a different Temple. Each Temple specialises in a specific expression of the art of death, from those that deliver it from afar using the pin-point accuracy of a high-powered sniper rifle to those that kill silently by poisoned blade.
The High Lords of Terra wield the Officio Assassinorum as a precision weapon, wielded only for the furtherance of grand strategy or the most terrible of vengeance. It is well known that a single bullet placed between the eyes of a rogue Planetary Governor as he addresses his followers can forestall an attempt at secession and avert a costly war of suppression. A sufficiently skilled infiltrator might spread such distrust and disorder within the ranks of an enemy army that it is split asunder, making it a far simpler task for the Imperium to defeat. No figure is immune to or safe from the Officio Assassinorum, from the highest ranked general to the most hidden of criminal lords