Editing Imperium Asunder Campaigns (section)

===13th===
Chaos warbands of the Behemoth Guard, the Judgement Bringers, and the Arms of Asura, gathering across Segmentum Tempestus for years in preparation, converge on the Providus Sector of the Unyielding Vigil, just below the Firewall. After a mercifully brief series of battles, the offensive appears to crumple, and the Loyalist forces chase their foes through the upper arch of the Segmentum, hoping to rout their enemies and deal a significant blow to the Warmaster's forces. Soon after these forces set sail, the Warp becomes turbulent, and the Silver Spears appear to strike at key targets within the Loyalist ranks. The Traitor Legions previously thought scattered turn to continue the fight, additional enemy forces revealing themselves to be waiting amidst the Tempestus, and the Crusade transforms into a protracted game of cat-and-mouse that stretches on through the first segment of M42.

As the Crusade in the upper Tempestus grinds on with no end in sight, the Crusader States watching with apprehension and uncertainty at the true severity of the situation, the ancient bindings that preserve the Firewall's glory begin to flicker and wane, and, for the second time in recorded history, a Great Maw begins to yawn open, this time in the contested zone of the Antonine Gulf, between the Unyielding Vigil and the Jade Empire. With speed that speaks of readiness, forces of the Bloodhounds domain, the Second Sons, the Fortress Worlds, and the Eyes of the Warmaster swarm the Gulf, establishing a series of fortified footholds in the mostly unclaimed territories. Forces from both nearby Crusader States are diverted to contain the onrushing threat, but internal difficulties on both sides slow down this process. Much of the Vigil's military arm is tied up on the Tempestus Front, while, in the Jade Empire, there are quarrels regarding the severity of the breach - many shadowy internal projects, considered essential to victory by their political proponents, hoard defensive forces further into the Empire, denying the Front their presence. Reinforcements from the other States are slow to respond, partially due to their own misgivings, but in no small part due to the worries of groups inside the Unyielding Vigil and the Jade Empire. In the Vigil, those engaged in sensitive heretek experimentation have no wish to evade yet more watchful eyes, and in the Empire, esoteric research foundations fear that heavy interference in the Realm could lead to the destruction of their projects.

This state of affairs continues for almost a century, the traitors advancing quickly to take the majority of the Gulf, eventually pushing upon the border worlds of both nearby Crusader States. It is amidst this atmosphere of distrust and chaos that an unexpected rallying cry emerges from the depths of obscurity. Borne back from the Front along with her fallen brethren, Sister Agathys Thera of the Order of the Dolorous Blade rises from the sleep of death, and the procession is diverted towards Amaranth. Bestowed with a gentle strength and authority, she enters the Tomb-Fortress of the Undying Scions, seeking an audience with Sarco Funerus himself. When she returns, she is another creature entirely: in her hands, she bears the flaming sword of the Emperor himself, ferried back to Amaranth along with his corpse. Her eyes blaze with fire and her command is absolute: the Servants of the Emperor will fight, and fight, and fight, until the day the Warmaster stands at the feet of his Maker. Promising not only to oust the traitors, but to cut like a blade into the depths of the Dark Imperium, she returns to the Front alongside the forces of a galvanized Unyielding Vigil. News of the Agathyian Miracle spreads quickly, and armies from across the Ultima Segmentum converge to fight and die for the dream of an Imperium once again in Loyalist hands. The traitor forces are deeply entrenched by now, however, given plenty of time to reinforce their positions by the indecision of the Crusader States, and pushing them back from whence they came will require yet another miracle.

All the while, the sprawling, disorganized wars fought in Segmentum Tempestus continue in earnest, a vast open maw slurping eagerly at the lifeblood of the Crusader States, constantly demanding more meat for the grinder. The Silver Spears, drawn together by the appearance of a being calling itself Slaanesh Incarnate to assault the worlds of the Eldar Empire, are seen less and less in battle with Loyalist forces, while an assemblage of Undying Scions successors fight their own battles with the Eldar, trying and failing to cut through the center of the xeno dominion under the rally of Idrias Stern, hoping the encircle the traitor Legions. The Orders the Broken Blades fight a bitter war of vengeance against the forces of Chaos, news of the Agathyian Miracle spurring many of them to push recklessly for the Fortress Worlds of the Iron Hearts. All around, traitors, loyalists, and mercenaries of all species continue to fight and die in the mire of Segmentum Tempestus.