Phonos - History: Little is known of the history of Phonos, not even its true name, but what little exists has been pieced together from data-fragments and the initial reports of the Explorators.At some point after the Horus Heresy, the Adeptus Mechanicus established a facility on an unclaimed world within the border territories of the Jericho Sector.The facility remained operational, subject to the will of the Jericho Sector's highest-ranking magos as all Mechanicus fiefs within the sector once were, for several thousand years. During that time, it adhered to a mandate of secrecy and isolation, limiting contact with the rest of the galaxy.Such a mandate is, typically, only employed by the Mechanicus to protect the most advanced and arcane of technology, such as archaeotech, rare configurations of a Titan combat walker, and other mighty war engines such as the unique and terrible Ordinatii.As the Age of Shadow descended upon the ancient Jericho Sector, the isolated facility cut itself off further, with all communication with the rest of the sector ceasing by the end of the 35th Millennium. It is believed that, at this point, the facility activated a stasis field generator contained within its structure, sealing itself off entirely.The last communication anyone received from the facility on the world now known as Phonos was a stream of unintelligible machine code, which forced its way between the minds of hundreds of astropaths, eventually stopping upon worlds containing datacrypts and archive repositories, cleansing them of any reference to the facility.In the latter half of 812.M41, an Achilus Crusade expedition accompanied by a contingent of Adeptus Mechanicus Explorators reached Phonos. As soon as the first report of Phonos' discovery arrived at Watch Fortress Erioch, the Omega Vault opened another of its many doors.Contained within the ancient, long-sealed chamber was a device, unrecognisable to all but the learned eyes of Watch Fortress Erioch's Masters of the Forge. The device appeared to be some form of control wand, apparently designed to interact with stasis field technology and believed to be linked to the facility on Phonos. Whether this is the case is yet to be seen, for nobody from the Deathwatch has yet managed to reach Phonos to employ the device and test the theory.Little more than speculation exists about the facility and its contents, but the extensive nature of the security measures involved have led many amongst the Adeptus Mechanicus and the Inquisition to believe that the facility contains some form of extremely advanced weapon or war engine.Given that other data-fragments tell of the "Omnissiah's voice" and "the killing noise," many who are privy to such secrets believe that the device may be some powerful form of Sonic Weapon, akin to an Ordinatus.If this is the case, then so deadly an engine of war would be a valuable asset to the defence of the Orpheus Salient, and a terrible threat if it fell into the hands of a group such as the dark magi of Samech or the Stigmartus.All that is known about Phonos for certain is that it is a world in the maw of the Great Devourer. When contact was lost with the Orpheus Salient, General Mikal Curas transferred his command to the Imperial Navy's Battlefleet Argo, and set out to Phonos to investigate. Three and a half solar weeks later, Battlegroup Argo arrived at the system's edge, to bear witness to a world being devoured.The Tyranids responded swiftly to Battlegroup Argo's presence; a beast interrupted while feeding, it struck with inhuman savagery, pouncing upon Imperial Navy squadrons and tearing them asunder with blade-limbs, feeder tendrils, bio-plasma blasts and pyro-acid sprays.Commanded by General Curas, Battlegroup Argo fought back valiantly, defiantly cutting apart the attacking bio-ships with salvo after salvo of continual fire.For eleven straight solar hours of fighting Battlegroup Argo held off the Tyranid advance as best they could, but outnumbered fifteen-to-one, they could only survive for so long, slowly losing one ship after another.The turning point came when the Mars-class Battlecruiser Cardinal Xian was boarded, its captain choosing to sacrifice the vessel by overloading her reactor rather than suffer the fate of death by Tyranid claws. With so powerful a vessel lost, the end was in sight for the battlegroup.The first that was heard of the fate of Battlegroup Argo came six solar months later, when the first of the straggling picket ships arrived back in Imperial space, having borne witness to the destruction of the Orpheus Salient's most lauded battlegroup, and the death of its supreme commander.