Shadow of the Emperor

The Shadow of the Emperor was a Space Marine Battle-Barge that served as the flagship of Corvus Corax, the Primarch of the Raven Guard Legion during the Great Crusade in the late 30th and early 31st Millennia. This flagship led the flotilla of the Raven Guard warships which comprised the XIX Legion's 27th Expeditionary Fleet. A notable feature of the Shadow of the Emperor, like all Raven Guard vessels, was the use of a special device known as a reflex shield, a modified version of the Void Shields that were utilised to protect most Imperial warships and installations. This device was an innovation from the planet Kiavahr, orbited by the home-moon of the Raven Guard. A void shield worked by using the power of the warp itself to displace incoming projectiles and high-energy attacks. The reflex shield changed the modulation of the warpcores that powered the void shields, calibrating them to a much higher tolerance and turning them inwards, so that matter and energy generated by the ship was redirected instead; all forms of radiation emitted by the Raven Guard’s ships could be displaced, rendering them undetectable to scanning equipment.

The advantages of the reflex shield technology fitted well with Corax’s ethos of war, allowing Raven Guard ships to approach their targets unseen, striking swiftly and decisively before withdrawing. The low energy requirement meant that such stealth could be maintained almost indefinitely. There was, however, a serious downside to their use. By employing its void shield generators for the reflex shields, a Raven Guard vessel had no defence against physical attack and it took time to power the generators from one state to the other, leaving a ship vulnerable for several minutes with neither its cloaking field nor its energy defence fully operational, hence the swift exit from orbit.

To the augurs and scanning arrays of an orbital base or ships throughout a star system, the Shadow of the Emperor would seem to melt away into the stars. To the naked eye they would have appeared to shimmer for a while, as the reflex shields engaged and shifted away the light reflecting from the ships’ surfaces, until eventually all such energy was being dampened and the vessels were rendered invisible. One other problem with the reflex shield, one that Primarch Corax had unsuccessfully laboured to overcome for many years, was the low energy threshold for which it could compensate. Reactors could only be run at half power without generating too much energy to be displaced, in turn reducing top speed and blinkering the ship’s sensor capabilities.

When making for a planet, the Shaodw of the Emperor would not take a direct route, it being a proscribed doctrine of the Legion to always approach a target by an indirect route. Instead it would take a circuitous, zigzagging path, using a timing and distance formula devised by the Primarch himself to maximise the damping effect of the reflex shields, enough to throw off any pursuer or sensor that might somehow detect them. Corax did not believe in taking chances when it came to moving freely and unseen.

Ultimate Fate
In response to the treachery of Warmaster Horus of the Loyalist Astartes in the Sons of Horus, Emperor's Children, World Eaters and Death Guard Legions at Istvaan III, the Primarch of the Imperial Fists Legion, Rogal Dorn, on the direction of the Emperor who had learned of Horus' actions from the Loyalist survivors aboard the Eisenstein, ordered 7 Loyalist Space Marine Legions to Horus' base on the world of Istvaan V to challenge the Warmaster. They would attack in two waves and fall under the supreme command of the Iron Hands' Primarch Ferrus Manus. The Legions comprising the first wave were the Iron Hands, Salamanders, and Raven Guard. The Legions comprising the second wave were the Alpha Legion, Night Lords, Iron Warriors, and a large contingent of Word Bearers that their Primarch Lorgar had stationed in the star system. Unknown to Dorn and Ferrus Manus, the Night Lords, Alpha Legion, Iron Warriors and Word Bearers had all turned from their service to the Emperor and pledged their loyalty to Horus, and been instructed to keep their new allegiance to Chaos a secret.

The Iron Hands, Salamanders and Raven Guard were deployed in the first wave of the assault on the planet while the Shadow of the Emperor and the rest of the flotilla of Loyalist vessels provided overwatch of the planetary assault, standing by in case they needed to provide assistance to the attack ground forces. After they secured the drop site, they were to have been followed by the arrival of the other four Legions. The first wave secured the drop site at heavy cost. Horus ordered his front line troops to fall back, tempting Ferrus Manus to overstretch his already thin lines. Against the advice of Corax and Vulkan, Manus led his Veterans against the fleeing Traitor Marines unsupported. Manus then brought his brother Fulgrim to combat. As the two Primarchs drew their weapons, the Raven Guard and Salamanders fell back to regroup and allow the second wave's Legions to advance and earn glory. However, as they returned they were mowed down by the four Traitor Legions that had landed to supposedly support them, thus revealing their new allegiance to Chaos. Horus then pressed his own attack and sandwiched the Loyalists between the two Traitor forces, killing most of them.

When the Traitors opened fire on the first-wave of Loyalist Astartes, the Shadow of the Emperor received their stand-to and distress broadcasts. It was cut off within a matter of minutes, probably being jammed. It was too soon for the reflex shields to be raised, and against such numbers that were arrayed against them, they would have been the only defence. The Terminus Est, under the command of First Captain Calas Typhon, was one of the few capital ships of the Death Guard Legion. When the Traitors revealed their treachery, the Terminus Est engaged and destroyed the Shadow of the Emperor. It is argued that this engagement was the earliest recorded conflict between Battleships that were specialised to carry Attack Craft. The engagement was swift and brutal, depriving the embattled Loyalist forces of any air support in the massacre that followed.