Editing Siege of Terra (section)

==Second Battle for the Lion's Gate and the Rise of the Emperor's Champion==
{{topquote|'''If you know what I did, then you would know the truth of it, brother--I can no longer die!'''"<br>"Oh, I know that. But ''I'' can! And ''that'' makes the difference.|[[Mortarion]] and [[Jaghatai Khan]]}}
With the Mercury Wall breached, the Siege was reaching its endgame. The loyalist forces were being slowly shoved back into the innermost circles of the Palace defenses. Comms were unreliable at best, supplies were running low, and sheer exhaustion and hopelessness were grinding the defenders down. Angron and the World Eaters were loose inside the Palatine, with the Sons of Horus following behind. The Death Guard occupied the Lion's Gate spaceport, taking over after the IV Legion's abrupt departure from the battlespace. As their tainted presence began to warp the port into a twisted mirror of Barbarus, Mortarion established himself in one of its command centers, using his new daemonic powers to amplify the currents of the warp and blanket the Palace in a psychic miasma of despair. The effect was so potent that even Rogal Dorn's legendary resolve was cracking under the weight of Mortarion's malignant influence. He had bent all his prodigious intellect and unmatched engineering skill toward transforming Terra into the mightiest fortress the galaxy had ever seen, and it had not been enough. Without Guilliman and the Lion and their legions, they were doomed to inevitable defeat.

Jaghatai Khan, frustrated by the passivity of static defense, decided to launch a counterattack on the Lion's Gate. His reasoning was sound: should the Dark Angels and Ultramarines arrive to relieve Terra, they would need a place to dock their voidcraft. Moreover, the powerful anti-orbital batteries of the Gate could be turned against the traitor fleet. With his decision made, he quietly assembled the V Legion while his friend and Army liaison Ilya Ravallion scrounged up every functioning tank she could find to support the assault. The Khagan also recruited the [[Orbital Plate|Skye orbital plate]] to serve as a shield against the guns of the traitor fleet, knowing that they would bombard his forces as soon as they were visible. The gathered tanks were formed into a new unit, the First Terran Armoured, and sortied alongside the V Legion, deployed into three massive attack groups. They shouldered their way through the outer defenses easily enough, using the tanks to smash the Death Guard's armored spearheads and deploying Stormseers to wipe out any daemons that manifested themselves. The V Legion's usual tactics of speed and shock power served them well in this stage of the assault, but things became much harder when they reached the spaceport. The battle turned into an attritional slugging match, with two of the three attack groups bogging down almost immediately. Only the group led by the Khagan himself made any headway, tearing through the massed ranks of the XIV Legion and breaching the Gate itself. The fighting grew steadily more desperate; the mortal tank crews were being pushed to their limits and beyond by the nature of the fighting, which required them to remain sealed inside their tanks at all times lest they fall prey to chemical weapons or warp-borne plagues, and the White Scars were stymied by the unnatural resilience of their foes.

As the battle continued to rage throughout the port's lower levels, the Khan infiltrated Mortarion's command center and challenged his brother to a duel. They fought like madmen, with nothing held back, but Mortarion's unnatural strength gave him the edge. He wrecked Jaghatai's armor, broke his arms and ankles, and smashed his face into a pulp. The Khagan stood up, laughing off wounds that should have killed him, and attacked again. He taunted Mortarion relentlessly until the Death Lord became enraged enough to make a mistake. The Khan skewered him, only for Mortarion to recover and bury his scythe in the Warhawk's chest. [[Just as planned|Which was exactly what the Khan had wanted him to do.]] Jaghatai had allowed Mortarion to deliver a killing stroke so that he could deliver one in return. He beheaded his corrupted brother, banishing Mortarion to the Warp and unleashing a psychic shockwave that staggered and disoriented the Death Guard. In the aftermath, Jaghatai succumbed to his wounds, triggering a berserker frenzy in his sons that drove the bewildered Death Guard out of the spaceport. The Khagan was carried out of the spaceport on a Leman Russ, where he was met by Ilya Ravallion. She sensed a spark of life within his broken and ravaged body and immediately had him taken to Malcador, who set his adepts to the task of healing the primarch.

Within the walls of the Palace, chaos reigned. As walls fell and city blocks were blasted into ruin, hordes of civilian refugees and Imperial Army units fled toward the illusory safety of the innermost districts, with the World Eaters and Sons of Horus at their heels. Some garrisons made lonely last stands, hoping to tie down the traitors as long as possible, while others collapsed and were overrun. As Dorn faced the inevitable, he summoned First Captain Sigismund and gave him a simple order: "Hurt them." As Sigismund made for the battlefield, he was greeted by Khalid Hassan, who brought him the Black Sword, an ancient and potent relic weapon forged in Earth's pre-Unification era. Sigismund took up the blade and went out to fulfill his father's orders, sworn now to fight for the Imperium as it would become, not as it had been. He cut down hundreds of traitor champions in single combat. Rumors of the warrior known as the "Black Knight" or "the Emperor's Champion" began spreading across the Palace, heartening loyalists and demoralizing the traitors. Many on both sides sought him out, either to join him or to kill him. Sigismund finally encountered Kharn, who challenged him to a rematch. Sigismund's cold, impassive fighting style disturbed the World Eater, who furiously tried to provoke a reaction in the First Captain. Unshaken, Sigismund fought Kharn to a standstill and cut him down, but not before the World Eater saw the truth of things in a rare moment of lucidity: Sigismund was the herald of a new kind of Imperial warrior, of [[Black Templars|a new Legion of fanatical, stoic, single-minded zealots]] whose relentless fury and inability to countenance defeat would wreak untold misery on a galaxy already groaning under the weight of aeons of anguish.

Meanwhile, Euphrati Keeler, who was now loose and alone in the ruins, used Sigismund as the inspiration for a new kind of army. Rallying the masses of civilian refugees and Army stragglers, she forged them into a militia armed with tools, a few lasguns, and their faith in the Emperor and sent them forth to fight the Traitor Legions. Though a hundred of them might fall in exchange for one traitor, Keeler regarded it as a fair exchange, for there were hundreds of thousands more to take their place. Garviel Loken, upon finding Keeler, was dismayed by her harsher, more brutal mindset. She justified it to him by arguing that this was the kind of army the Imperium would need in the future: [[Imperial Guard|an army of millions, even billions of humans, united by their unwavering faith in the Emperor and their hatred for the alien, the mutant, and the traitor]].