Horus Heresy - Horus Triumphant: After the killing had stopped and the dead were gathered into great funeral pyres across the broken desert of the Urgall Depression, the once-grey skies of the planet burned orange with the reflected glow of a thousand pyres. The firelight bathed the rippling, glassy sands in a warm radiance, and towering pillars of black smoke from the burning corpses filled the air. Thousands of Astartes loyal to Horus gathered before a great reviewing stand, constructed by the Tech-priests of the Dark Mechanicus with astonishing speed. As the sun began to sink beyond the horizon, the smooth black planes of the stand shone with a blood red glow. The stand was erected as a series of cylinders of ever decreasing diameter, one standing atop another. The base was perhaps a thousand metres in width, constructed as a great grandstand upon which the Sons of Horus stood, their pre-eminent position as the elite of the Warmaster in no doubt after this great victory. Each warrior bore a flaming brand, and the firelight cast brilliant reflections from their armour.Atop this pedestal of flame was another platform, occupied by the senior officers of the XVI Legion. Above the senior officers of the Sons of Horus stood the Traitor Primarchs. The sheer magnificence of such a gathering of might was breathtaking. Seven beings of monumental power stood on the penultimate tier of the reviewing stand, their armour still stained with the blood of their foes, their cloaks billowing in the winds that swept the Urgall Depression. Finally, the uppermost tier of the reviewing stand was a tall cylinder of crimson that stood a hundred metres above the Primarchs. Horus stood on top of it, his clawed gauntlets raised in salute. A furred cloak of some great beast hung from his shoulders, and the light of the corpse pyres reflected from the amber eye upon his breastplate. The Warmaster was illuminated from below by a hidden light source, bathing him in a red glow that gave him the appearance of the statue of a legendary hero, as he stood looking down on the endless sea of his followers from the towering platform.As the sun finally dipped below the horizon, a flight of assault craft roared over the Urgall Hills, their wings dipping in salute to the mighty warrior below. Solid waves of cheering crashed against the reviewing stand, howls of adulation torn from tens of thousands of throats. No sooner had the aircraft passed overhead than the massed Astartes began to march around the reviewing stand, their arms snapping out and hammering their breastplates in salute of the Warmaster. At some unseen signal a flame ignited on the northern slopes of the Urgall Depression and a blazing line of phosphor leapt across the ground in a snaking arc that described the outline of an enormous blazing eye upon the hillside. The adulation soared to new heights as the Eye of Horus seared itself into the sands of Isstvan V, the Warmaster’s forces roaring themselves hoarse in his praise. Super-heavy tanks fired in salute of Horus, and the towering immensity of the Dies Irae inclined its massive head in a gesture of respect. The ashes of the dead fell like confetti over Horus' mighty army as thousands of Traitor Astartes cheered, their cries of "Hail Horus! Hail Horus!" resounding long into the darkness.Barely a handful of Loyalist Space Marines escaped with their lives from Isstvan V to bring dreadful word of the further betrayal of four more Space Marine Legions to the Emperor. A critically wounded Corax made the dangerous journey through the Immaterium back to Terra, arriving 133 days after departing the Isstvan System and finally reaching the Sol System -- the heart of the Imperium -- to seek audience with the Emperor. Vulkan was missing and presumed dead, though he would later reemerge after a harrowing journey back to Terra himself, to lead his Legion once more. The Salamanders, along with the Iron Hands and the Raven Guard, would spend the remainder of the Horus Heresy rebuilding their decimated Legions and were too weakened to play any further role in the great conflict.In the days after the battle, the Traitor Legions salvaged a large number of vehicles, wargear and other war materiel from what the Loyalist Legions had left on the field. This salvage was repaired and modified for the Traitor Legions' use and then put back into frontline service to be used against the Imperium. Some of this equipment would still be in service with certain Chaos Space Marine warbands in the late 41st Millennium. Orbital space around Isstvan V was busy as the vessels of 8 Legions assumed formation prior to transit to the system jump point. Over 3,000 vessels jostled for position above the darkened fifth planet, their holds bursting with warriors sworn to the service of Horus. Tanks and monstrous war machines had been lifted from the planet with incredible efficiency and an armada greater than any in the history of the Great Crusade assembled to take the fire of war into the very heart of the Imperium.In the days after the Drop Site Massacre, Horus called for a conclave of the Primarchs of all 8 of the Traitor Legions aboard his flagship, the Vengeful Spirit. Five of the Primarchs, including four who had fought at Isstvan V, met in person, including Horus, Fulgrim, Angron, Mortarion and Lorgar. Three appeared through the use of hololithic emitters that transmitted their signals through the Warp, including Perturabo, Night Haunter and Magnus the Red, who had only recently joined the Traitors after the Scouring of Prospero when the broken remains of his XV Legion had been transported by Tzeentch into the Eye of Terror to the Planet of the Sorcerers. The Thousand Sons, bitter at what they perceived as their betrayal by the Emperor, now willingly became the eighth Traitor Legion. The council of Traitor Primarchs made their plans for the next step in their war against the Emperor and then each Legion went its way according to its assigned role.The fleets of Angron, Fulgrim, Mortarion, Lorgar and Horus' own Legion would rendezvous at Mars, now that word had come from the Tech-priest Regulus, the Mechanicus' liaison with the 63rd Expeditionary Fleet, of that planet’s fall to Horus’ supporters within the Mechanicus during the internecine conflict known as the Schism of Mars. With the manufacturing facilities of Mondus Gamma and Mondus Occullum wrested from the control of the Emperor’s forces, the forges of Mars were free to supply the Warmaster’s army. The eager warriors of the Alpha Legion were singled out by Horus for a vital mission, one upon which the success of the entire venture could depend. Following Horus' manipulation of Leman Russ into assaulting the homeworld of the Thousand Sons, the Space Wolves were known to be operating in the region of Prospero. In the nearby system of Chondax, the White Scars of Jaghatai Khan were sure to have received word of Horus’ rebellion and would no doubt attempt to link up with the Space Wolves. Horus could not allow such a grave threat to appear, and so the warriors of Alpharius were to seek out and attack these Legions before they could join forces.The Night Haunter’s fleet had already departed, bound for the planet of Tsagualsa, a remote world in theEastern Fringe that lay shrouded in the shadow of a great asteroid belt. From there, the Night Lords’ terror troops would begin a campaign of genocide against the Imperial strongholds of Heroldar and Thramas, star systems that, if not taken, would leave the flanks of the Warmaster’s strike on Terra vulnerable to attack. The Thramas System was of particular importance, as it comprised a number of Mechanicus Forge Worlds whose loyalty was still to the Emperor. This campaign would also serve to tie up the dreaded Dark Angels Legion, so that the forces of the Lion wouldn't be brought to bare against Horus and his upcoming campaign against Terra.The ships of the Iron Warriors prepared to make the journey to the Phall System where a large fleet of Imperial Fists vessels were known to be regrouping after a failed attempt to reach Isstvan V in time to join the Loyalist assault. Though Rogal Dorn’s warriors had played no part in the Drop Site Massacre, Horus could not allow such a powerful Loyalist force to remain unmolested. The enmity between bitter Perturabo and proud Dorn was well known, and it was with great relish that the Iron Warriors set off to do battle with their old rivals. With his flanks covered and the Space Marine forces that could potentially reinforce the heart of the Imperium soon to be embroiled in war, the Traitors were ready to unleash 7 Terran years of devastating civil war upon the Imperium in the name of Horus and the Dark Gods.