Grail Abyss - History: Separated from the remote Coronid Reach sub-sector by the mysterious and dreaded Coronid Prohibition Zone, the Grail Abyss lies to the galactic northwest of the heavily-populated worlds of the Manachean Commonwealth and to the galactic north of the Cyclops Cluster.The Grail Abyss forms the very edge of the Segmentum Obscurus and known space; beyond its borders lie only drifting star systems accessible to the vagaries of relatively stable Warp-passages from more coreward planets -- among these outer realms being such systems as the infamous Isstvan System or Ultima Ectosa, the furthest star to the galactic north known to possess an Imperial colony.The Grail Abyss suffers from a psychic emptiness in local Warpspace, which has given it its name as travelling in this region compares to the exploration of the antique seas of sacred Terra. In conjunction with other stellar hazards, this phenomenon makes travel in the region unreliable and indeed more difficult than reaching more far-flung planets such as those of the Coronid Reach. As a result, Human colonies within the Grail Abyss are few and far-flung, mere candle-points flickering in a sea of night.All these difficulties however do not seem to have hindered Human colonisation in the Dark Age of Technology, as the Grail Abyss possesses advanced Human settlements and worlds as developed and populous as those of the Cyclops Cluster. With the breakdown of communication and interstellar travel across Human space that accompanied the dawn of the Age of Strife, many of the worlds of the Grail Abyss regressed significantly, and some fell prey to unidentified cataclysmic events which still cause much puzzlement among Imperial scholars.Contrary to the more powerful worlds of the Manachean Commonwealth, the worlds of the Grail Abyss never suffered from the baleful intentions of the xenos Mitu Conglomerate as it was by then firmly in the hands of the Orks who had colonised several planets. In the 30th Millennium, as the Great Crusade reached the northern marches of the galaxy, the Grail Abyss was mostly brought into the folds of the sprawling Imperium of Man through the efforts of the 7th Expeditionary Fleet lead by Lord Commander Suleiman Grimm of the I Legion which had already liberated great parts of the Cyclops Cluster.During the events of the Horus Heresy, the Grail Abyss was somewhat spared the bloodier events or the devastation unleashed among the Cyclops Cluster as the Traitors never truly deployed in force in the region. Likewise, the Loyalists deployed very few forces in the Abyss as its worlds were considered too isolated and ultimately less important on a strategic level in the Coronid Deeps region than those of the Cyclops Cluster and the Manachean Commonwealth. With only a finite amount of warships at its disposal, the Imperial Army's Armada Imperialis preferred to focus on the defence of more strategically important worlds, and so the Grail Abyss was largely abandoned to its fate.The isolation and Warp vagaries of the Grail Abyss, however, caused it to become a ready refuge for fleeing Loyalist elements who had escaped the Drop Site Massacre of Isstvan V. Having regrouped and in some cases even resupplied, these Loyalist splinter groups would mostly choose to flee to more defensible systems; however some chose to remain and fight the Traitors like the grim Autek Mor of the Iron Hands Legion and his vessel, the Red Talon.