A wave of conquest
With the Fall of Cryxis IV the stygian empire began another wave of conquests. World after world fell to chaos with the Imperial fleet reeling there was little the Imperium could do to stop the wave of conquests. Imperial worlds mustered what resistance they could and tried to bleed the Stygian Guard to weaken them all the while sending out desperate pleas for aid
Within a year however imperial reinforcements were arriving in the sector to try and stem the tide. Moreover a number of worlds had began mass conscription programs to combat the oncoming Stygian tide. In particular the hive world of Anglia Prime raised a force of nearly 28 million in a year. However with the first war machines of the Dark Mechanicum forgeworld of Cryxis IV starting to reach the front lines Stygian forces were able to keep up their implacable advance
Signs of Hope
The next year saw still more advances made by the Stygian Empire, but the pace of conquest was slowing. More and more Imperial reinforcements were making it into the sector, enough that the Imperial fleet was beginning to conduct raids on the Stygian Empires shipping lanes. Another reason for the slowing of the Stygian Empires advance was the great strain their quick conquests had put on their supply lines. The most noticeable effect of this for Imperial forces was the composition of the Stygian forces. The Stygian Guard remained primary structured like a Imperial guard regiment, but now being seen more often were militia armies made up of cultists, mutants, and daemonic war engines. While fearsome in their own right they lacked the discipline and training the Stygian Guard had. though it was foolish to underestimate their potential. Still the Stygian advance continued in part due to the increasing number of psychers fighting for the Stygian empire. These psychers would often summon daemonic aid further increasing the severity of the warp storms beginning to engulf the sector.
The Following year brought more reinforcements to the Imperials in the form of ships regiments and even a few astartes strike forces, including a large detachment from the Apocalypse Angels. Finally on the worlds of Belruss II, Chosan III, and Quatel Prime, the Imperium was able to halt the advance of chaos.
With the Stygian Empire momentarily checked, sector command bagan to take stock of the overall strategic situation. Thirty four worlds were now part of the Stygian empire. Intelligence reports confirmed that each of these worlds was being fortified forming multiple rings of steel around the heart of the Stygian empire. Cracking those defenses would be long and bloody. Still a chaos pocket empire could not be allowed to exist in the sector plus Intelligence reports were revealing other potent hazards stemming from the Stygian Empire. The tithe to Lord Magwar was learned of and Imperial authorities calculated that within three year the Alpha Legion would have stockpiled enough to do this again in another sector, and perhaps anther two sectors within eight years. Such a massive upheaval threatened the entire segmentum. Of other concern was the Stygian Empire was acting as a beacon for every renegade and chaos worshiper in the segmentum drawing them to the fighting. It was learned Lord Magwar was helping equip these renegade warbands in exchange for oaths of fealty and other favors. It was determined that the 7th Hydra under Lord Magwar could not be allowe to garner the support and power he needed to pose a threat to the Imperium on the level of Huron Bleckheart, or Abbadon. With the new influx of reinforcements The Imperium would go on the offensive and crush the Stygian Empire.