Editing Negators (section)

===The Vanaheim Campaign===
The Vanaheim Campaign was fought in multiple stages by a number of belligerents, the Negators only entering the arena relatively late into its story. The fist fighting of the Heresy occurred on the system's central Forge World of Vanaheim, where the Magos Dominar Harrion Vendrick, long lost to the daemon-Warped cult of Gengrat, initiated the suddden betrayal of its Storm Hammers' garrison by the local Skitarii Legions. The chaos and confusion of the first hours of the battle cost many Astartes their lives, and Engerand's sons soon found themselves besieged, their numbers sorely diminished by the ruthless nature of Harrion's betrayal. Fresh horrors born from the twisted Dominar's newfound freedom to experiment became common occurrences as the first days of what would come to be called the First Siege of Vanaheim dragged on into months.

Reprieve came for the Storm Hammers when the Undying Scions, retreating from the galactic rim, transitioned out of Warp in the Vanaheim System, intending to resupply and gather any forces they could muster for the battles ahead. Finding that he and his sons had stumbled upon an active warzone, Sarco quickly ascertained that the servants of the Dominar were the traitorous party, and initiated a full-scale assault on the system, driving Vendrick's Skitarii Legions back and giving the Storm Hammers some well-earned breathing room. Though the Scions achieved their initial goal of rescuing the stranded Storm Hammers, their original task proved more difficult. The Magos Dominar had had ample time to inflict his heresies upon the human populations of the Vanaheim System. The Undying Scions found themselves struggling to take what they needed from the resource-rich worlds of the forge system. Rather than fight a war of destruction against their foes, Sarco and his allies were forced to battle defensively, making small, surgical strikes into locations thought least defended, their main forces occupied with the task of fighting over Vanaheim's major spaceports. The Primarch's hopes were that he and the Storm Hammers could liberate enough supplies from the system without incurring needless casualties, before leaving the planet to the traitors. These hopes appeared dashed when, long before even the kindest logicians could dub the Astartes forces ready for launch, the pursuing Negators fleet of the Primarch Aodhán emerged from the Warp at the edge of the Vanaheim System.

Intent on keeping the Scions at Vanaheim, Aodhán's Legion descended on the primary conflict zones, focusing their efforts on disrupting any and all attempts to resupply by either Loyalist Legion. The Negators excelled at the kind of mobile warfare Sarco had been forced into fighting, and soon many precious resources were considered all but unreachable, and the Loyalists fell back on more conventional, less opportunistic tactics that were more suited to their skills, but far less suited to the situation they found themselves in. Many close bonds were formed between the Scions and the Astartes of the Storm Hammers 6th Chapter upon these battlegounds, the Hammers providing integral support ops to ensure that their lumbering allies were not cornered and picked apart by skilled teams of Venators. The the Loyalist forces held many entrenched positions far into the campaign, an effective withdrawal seemed impossible, and the Primarch of the Undying Scions prepared a final gambit in the case of his demise and Vanaheim's fall to traitorous hands. Consolidating much of his forces in the primary manufactorum complex of Vanaheim, Sarco ordered that the vast construct's plasma reactors be readied for detonation. The Primarch judged that Aodhán would not be able to resist a decisive blow against Sarco and the majority of his Legion, and would be drawn personally to the Hive. Funerus' resolve was as steel - if he could not defeat Aodhán in combat, he would not allow his brother to escape Vanaheim alive, razing the entire central Hive in an explosive torrent of superheated plasma.

Had Sarco's plan come to fruition, the course of history may have been unrecognizable. The Primarch of the Undying Scions was spared the fury of his own plan by the timely arrival of Engerand and the battered remains of the Storm Hammers Legion, scarred by a trail of battles from Cadia to Vanaheim and arriving in the system to replenish their numbers with the Legion garrison. Just as Sarco had before, Engerand transitioned out of the Warp to the sight of a realm flung into Chaos, torn asunder by infighting. The Negators made no attempts to disguise their nature as traitors, and the Storm Hammers were quick to come to the Scions' aid. Lead by their Primach himself, reduced some in stature but none in fury by the replacement of his leg with bionics, the Legion initiated a series of rapid assaults on the major spaceports that littered Vanaheim's surface, dealing a crushing blow against the Skitarii that held many of these positions. Engerand was met in battle by Dominar Harrion, who had by now transformed himself through heretek foulness into a being of coruscating Warpflesh and twisting metal. The battle was not a simple one, and many believe that Harrion was preparing for some further transformation, but ultimately Engerand bested the creature, striking its engorged cranium across the tundra of Vanaheim and plunging the Dark Mechanicus forces infesting the planet into disarray and infighting with a single swing of his hammer. Now forced to consider their own exit strategy, the Negators' attention was turned away from the Undying Scions, and the battered Legion was able to make for Terra, their exit covered by Engerand's forces, who swore to hold Aodhán's Legion at Vanaheim as long as possible.

The winding streets and densely-packed foundries of Vanaheim's Hives were favourable to both Legions' preferred tactics, and the fighting in this stage has been noted by historians to be particularly bloody, even by the standards of the Heresy. Now effectively trapped on the Forge World with the Storm Hammers, the Negators fought to separate and draw out Engerand's sons, hoping to eventually exploit an opening and carve a way off-planet by taking one of the primary spaceports once its defenders finally overreached. Engerand's will was set, however, and his Marines stood firm - it was only when the Dark Mechanicus assets scattered on Vanaheim begin to show signs of uniting under new leadership that the Storm Hammers considered that their position would eventually become untenable, and they fell back on Sarco's last, unused gambit.

Funerus' estimation of his brother proved correct. When Engerand centralized his veteran companies in the central Hive of Vanaheim, Aodhán was soon reported to be personally leading an assault on the war-torn megatropolis. It is a testament to the sheer ferocity and power of the Primarch that, even acting entirely as predicted, Aodhán's assault on the city was nearly a decisive Negators victory, the Giantslayer personally tearing through all opposition to his Legion. Seeking out his brother amidst the steaming foundries of the Hive's greatest manufactorums, Aodhán engaged Engerand in single combat, and though the Storm Hammer was mighty and he brought blows raining down upon the traitor, it soon seemed clear that Aodhán would overwhelm Engerand. In truth, however, Engerand's personal loss was suffered for the sake of the battle at large. Sending the immense furnaces of the city into a cascade of chain reactions that threatened to consume much of the Hive, Engerand activated the teleport beacon integrated into his Terminator armour, leaving Aodhán to be consumed by his own overconfidence. 

Hive Asgier-001 vanished in a pillar of fire that scorched the very atmosphere of Vanaheim, forever blackening one of its moons. Their objective accomplished, the Storm Hammers retreated into the void and departed for Terra, breaking free of the ongoing orbital conflict with Negators forces during the utter chaos of the detonation. Aodhán was presumed dead by his brother, until he resurfaced at the Siege of Terra, his armour battered and seared with heat, and his skin seeming to shine brighter than before.