Father Nurgle was able to claim a Primarch and his legion as his own! Who was this Primarch and how was he able to do this? Let’s take a look!Without the Emperor there to save him from the toxins, Mortarion gave in to Chaos and Father Nurgle took over.
Via our good friends at Lexicanum
Horus found Mortarion more difficult to bring to his cause than either Angron or Fulgrim, and for a time it seemed the Warmaster may have failed to convince the Lord of the Death Guard. However Horus at last found a chink in Mortarion’s armor, he was beginning to see the Emperor as having been corrupted with power and now was just another tyrant drunk with power.
Indeed, Mortarion had become disgusted with what exactly the Emperor was, considering him a Warp-tainted “aberration” like his tyrant adopted father. Horus also used Mortarion’s distrust of the Warp to his advantage, arguing that the Emperor had used the Warp in the creation of the Primarchs. Horus eventually used these doubts to bring Mortarion to his cause. Mortarion led his Legion in their betrayal of the Imperium at the Battle of Isstvan III and Drop Site Massacre. He later came to blows with Jaghatai Khan on Prospero after failing to convince him to join with them in rebellion. During the fight the two Primarch’s were able to challenge the other, with the Great Khan proving faster and the Death Lord proving more durable.
Following the battle, Mortarion abandoned his pursuit of the White Scars and instead began a spiteful purge of the systems surrounding Prospero. During the purge, Mortarion encountered a Daemon possessing the body of a woman and was forced to kill it using his innate psychic abilities despite it being against Imperial (and by this point, his very own) dogma. Realizing that the Emperor had lied to him about the Empyrean, Mortarion vowed to master it.
Mortarion next appeared during the Battle of Dwell, summoned by Horus alongside Fulgrim to aid him in gaining the powers of the Emperor on Molech. During their meeting, Mortarion survived an assassination attempt by Shadrak Meduson, who assaulted the Primarch’s with a trio of Fire Raptors. Later in the Battle of Molech, Mortarion sacrificed several of his Deathshroud warriors to allow for the resurrection of Ignatius Grulgor.
By the time of the Battle of the Kalium Gate late in the Heresy, Mortarion’s forbidden knowledge had grown considerably. He experimented with both Xenos and Chaos artifacts, vowing to remain pure through understanding. At this same time he was tasked withHorus to find and destroy the White Scars, who had been harrying the traitor lines since the events on Prospero.
Mortarion was initially reluctant, but was moved by Horus’ declaration that he was the only Primarch the Warmaster still could rely on and was eager to settle the score with the Khan anyway. In the subsequent Battle of Catallus, the joint Death Guard-Emperor’s Children fleet led by Mortarion cornered the White Scars fleet at the Dark Glass artifact. But as Mortarion boarded Jaghatai’s flagship, the Swordstorm, he discovered the ship abandoned save for a contingent of suicidal Sagyar Mazan warriors. Worse still for the Primarch, the reactors of the Swordstorm had been set to overload and the Khan had since evacuated to the Battleship Lance of Heaven, which was leading the escape of the loyalist fleet into the Webway.
Unable to escape thanks to the Sagyar Mazan and the vessels reactivated Void Shields, Mortarion led the massacre of the Scars suicidal rear guard while directing his fleet to combine its fire and reduce the Swordstorms shields. When the shields were depleted shortly after he personally killed Torghun Khan, Mortarion barely teleported off the Swordstorm before it exploded. Following the battle, Mortarion realized that his divided fleet had hampered the war effort and ordered Eidolon to find Calas Typhon and his splinter fleet.
After these campaigns, Mortarion rejoined the primary Death Guard fleet under Calas Typhon, who was waging the Dark Angels fleet in a campaign of misdirection in the aftermath of the Battle of Perditus. Eventually with the entire Death Guard fleet, Mortarion set off to Terra to join the siege. Unfortunately the fleet was caught in an impenetrable warp storm, the navigators not being able to find a way through the warp or a way back into real space.
The fleet was reduced to drifting, and in that time the Destroyer came. The plague that came could not be resisted, something that terrified Mortarion and the Death Guard. It transformed them into bloated mutants, yet none could die, their own body being their undoing. None suffered more than Mortarion, for it was like being on the mountain top again, surrendering to the toxins, but this time without the Emperor to save him. Eventually, Mortarion could suffer no more and gave himself to Chaos. Father Nurgle responded and took the legion and Mortarion as his own.
What emerged from the warp bore little resemblance to what had gone in. The Marines’ once gleaming armour was corroded and shattered, barely containing their bloated, pustule covered bodies. Their weapons and armour were powered by the energies of Chaos and they became known as the Plague Marines, although they would still use the name Death Guard. After Horus was defeated, Mortarion led his forces, in an ordered formation, back to the Eye of Terror.
Mortarion claimed the Plague Planet as his new world and it is ideal for launching attacks on the real world. He shaped it so well that Nurgle promoted him to Daemon Prince. Mortarion got what he wanted, a world of his own. He ruled over a toxic death world of poison, horror and misery. He had come home.
