Officio Assassinorum - History: The Imperial Assassins are the hidden blades wielded by the High Lords of Terra. They are the slayers of kings and false messiahs, the bane of Traitors and rebels across the stars. Once an agent has been despatched, they are as relentless and inescapable as the march of time itself. Every facet of their impeccable training is turned to the business of a single kill. Though the temples of the Officio Assassinorum are shrouded in the utmost secrecy, all men and women of influence fear the shadows they cast, for their operatives are the Emperor's justice made real. In a realm the size and scope of the Imperium, it is all too common for planets to escape the vigil of the High Lords.With communication and travel at the mercy of the Warp's shifting tides, a populace can go for ten, twenty, even a hundred standard years without being contacted by the wider Imperium. It is a fragile system indeed, and given the crushing grind of much of Imperial life, one that has seen many worlds fall into the thrall of heresy. Left to fend for themselves against a hostile galaxy, it is easy for a planet's citizenry to harbour the seeds of corruption. A world may fail to pay its Imperial tithes, allow its psyker containment routines to slip, or come under the rule of an unsanctioned or secessionist planetary government. Some simply crave independence away from the dictates of the Administratum, the Ecclesiarchy, and a galaxy ruled by twelve faceless figures in the name of a distant God-Emperor.Regardless of whether the new order is benevolent or tyrannical, its orchestrators make themselves targets for the most violent of retributions. Though their government may thrive in the short term, word will eventually reach the adepts of the Imperium of their disobedience. Sometimes the resultant confrontation leads to open war, but it is just as often resolved by covert means. Coercion, bribery, threats, blackmail and murder are all weapons in the armoury of those whose iron grip defines the realms of Mankind. To this end, the Imperium has developed several institutions to exploit these weapons to their fullest; ancient organisations that trace their history back to the Great Crusade and the very birth of the Imperium. One such organisation is the Officio Assassinorum.The Assassins of the Imperium are able to change the fate of worlds with the pull of a single trigger. Where the length of the Emperor's reach needs to be made abundantly clear, a Vindicare Temple sniper will put a bullet in the target's head whilst the errant individual is surrounded by his followers.If the traitorous creed has spread to an entire organisation or military force, an Eversor Assassin will instead be set loose; a bio-enhanced berserker that will slaughter dozens if not hundreds of rebels alongside the key individual they have been sent to slay. Should the deed require more subtlety, an operative from the Callidus Temple will instead be despatched; in such cases it is all but impossible to detect the presence of these shape-shifting Assassins until the deed is done. If the target is a psyker, one of the rare and fearsome Culexus Assassins will be sent to hunt them down -- beings with a strange void in place of a soul that makes them the bane of all who treat with the Warp.The weapons of the Assassins range from simple knives and garrotes, to exotic neural shredders and phase swords that can cut through armour and force field alike. Even barehanded, these operatives are lethal foes; each is trained extensively in unarmed combat and is more than capable of fighting their way free from the mayhem that ensues from their kill.Returning to their masters, they are extensively debriefed and examined before being given a new mark and mission to accomplish. In this way, each Assassin is locked into a constant cycle of headhunting that spans the breadth of the Imperium, reforging the fragile chains of Imperial rule even as the Era Indomitus in the 41st Millennium breaks them apart.