"Locate those long-range plague monstrosities and eliminate them!"
The veterans immediately made the correct tactical assessment. The engines of the Stormraven gunships roared as they pulled into a steep climb, banking hard toward the twisted, corrupted jungle.
The profane plague-spitters were glaringly obvious. These warped bio-cannons were the product of vile experimentation by the Death Guard's virulence apothecaries, who had engineered local fauna to gestate contagions. Infected by the warp-spawned blights, the massive beasts had grown deformed and hideous. They could regurgitate their own viscera, bloated with pus, diseased blood, and necrotized meat, from maws spanning over two meters wide, hurling them up to three kilometers away. Though these plague-wrought organisms could not rival the spore-projecting bio-beasts of the Tyranid Hive Fleets, they posed a catastrophic threat nonetheless.
The organic artillery shells carried a horrific rot capable of liquefying all organic life within seconds. Even shielded by power armor and blessed with the physiology of a demigod, an Astartes could not endure such virulent toxins for long.
A Stormraven had just unleashed its payload of Hellstrike missiles when several beams of grayish-green light lanced out from the canopy, detonating the gunship mid-air into a roaring fireball.
Down on the landing field, another Stormraven, its hull scorched black and marred by unnatural, rapid rusting from multiple missile impacts, groaned as its assault ramp slammed open. Though the gunship had not fully touched down, the Keshig warriors accompanying their Primarch leapt directly from the bay into the dirt. They surged toward a nearby macro-drop-pod, where rows of sleek scimitar jetbikes were secured. Far more costly than wheeled attack bikes, these grav-craft possessed unparalleled maneuverability.
Then came Jaghatai, plunging directly out of the Stormraven's hold astride his personal jetbike.
The Primarch's roar echoed across the battlefield.
"Mortarion! You selfish, Chaos-spawned filth! Sons of the White Scars, show this traitor the wrath of Chogoris! Bury him and his lackeys beneath the dirt! Let the enemies of the Emperor know fear!"
A foul cloud of spores churned across the sky. Throngs of White Scars warriors, brandishing promethium-fed hand-flamers gifted to them by the Salamanders, charged into the swelling hordes of Plague Zombies.
A newly inducted Neophyte of the Chapter severed a deformed, grotesque corpse with his chainsword, only for dozens of maggot-like tentacles to burst from the severed meat and lash around his left leg. The plague-ridden parasites instantly caused the ceramite of his greave to brittle and decay, eating their way into his flesh.
"For the Emperor and the Khan!" the Neophyte bellowed. He drew his meltagun and vaporized his own left leg along with the blasphemous tentacles. The rot immediately attempted to flood his bloodstream through the raw wound. His transhuman anatomy fought fiercely to suppress the horrific infection; the blood dripping from his stump hissed as it hit the dirt, instantly turning into a grayish-green sludge of decay.
Three meters away, a legionary veteran's master-crafted tulwar clashed against the rusted plague-axe of a Death Guard Plague Marine. The foul edge of the axe caused acrid green smoke to bloom where it scraped against the Chogorian's ceramite plate.
"Purge them with fire!"
The Khan's command pierced the deafening roar of battle. Warriors equipped with promethium heavy flamers instantly formed a defensive ring, bathing the earth in promethium and scorching black pathways through the fungal groves.
Suddenly, a four-meter-tall Beast of Nurgle erupted from the earth. The pustules carpeting its flabby back erupted in a downpour of acidic fluid. Two White Scars were caught in the caustic spray, their agonizing shrieks tearing through their vox-grilles. Their power armor dissolved into slag, the virus burrowed deep, and their flesh underwent horrific mutations as jagged bone-spurs tore outward through their skin.
The Beast of Nurgle rolled its bloated, boil-covered tongue, swaying as it turned its bulbous eyes toward the other White Scars. Before the mutated battle-brothers could succumb entirely, two plague-infected bolt shells struck them from the flank, shattering their helmets and detonating their heads.
Then, Jaghatai's jetbike descended like a thunderbolt. As his power dao cleaved downward, the resulting ionization storm split the monster completely in two. Its boiling organs were vaporized by the weapon's disruptive energy field before they could even hit the ground.
The Khan raised his relic blade, its edge dripping with foul ichor, reflecting the pyres of war to illuminate the entire front.
"Cut down these wretched traitors! For the glory of the Emperor!"
The White Scars raised a deafening war cry. Flashing blades and roaring bolters tore chunks of rotting flesh from the advancing Death Guard.
With a subtle gesture from Mortarion, several Deathshroud Terminators guarding his flanks materialized from the burning cloud of spores. The plague censers embedded within their Cataphractii armor exhaled thick, yellow-green smog as they silently swung their massive scythes. In a blinding flash of rusted steel, over a dozen White Scars were cut down, the virulent contagions coating the scythe-blades instantly rotting their flesh. A bizarre, droning chorus seemed to whisper in the ears of the dying:
"Join us… accept the Grandfather's embrace…"
The Keshig gunned their jetbikes, driving hard into the Deathshroud. A gleaming plasma talon pierced the chest cavity of one Terminator, only for the rider to find the tip of his power spear corroded and snapped away. The aura of decay radiating from the Deathshroud was so potent that even power weapons struggled to withstand its touch.
But then the Khan blurred past like a stroke of lightning. His dao traced a flawless, effortless arc; three Terminator suits, along with the corrupted husks within them, were cleanly cloven in twain. Corrupted, blackening blood erupted from the perfect cuts.
"The spirits of the ancestors guide the Khan's blade!" the warriors shouted, invoking their ancient tribal war cries.
Several melta blasts punched through the silent servants of Nurgle. Though the blessings of the Plague God rendered them monstrously durable, the concentrated firepower surpassed the threshold of their unnatural resilience. Their ruined flesh could no longer sustain them, collapsing into mounds of putrid meat.
Jaghatai suddenly wheeled his jetbike, charging toward the northwestern flank. There, a Plague Sorcerer waved a staff pulsing with a sickly green light, trapping several White Scars within its radius. Each swing of the staff, which was inset with seven rotting eyeballs, unleashed skull-shaped clouds of toxic miasma. The lethal vapor bypassed the seals of their power armor, rotting their bodies from the inside out within seconds.
Two White Scars tore off their helmets in agony. Their features contorted as they opened their mouths to cough, but no air would come; twisted, mushroom-like fungal spores erupted from their throats, which then withered and popped to release more of the lethal virus.
"Coward!"
The Khan's blade sliced cleanly through the toxic fog. The Plague Sorcerer desperately raised his staff to parry, but the strike severed both the weapon and his right arm at the shoulder. Before the black blood could spray, the dao ran him through his distended belly, a secondary flick splitting him into two halves. Nearby warriors instantly unleashed their heavy flamers, consigning the remains to the fire.
Then, Mortarion's scythe, Silence, the weapon that had accompanied him for ten millennia, tore through the burning miasma. The foul hurricane whipped up by the reaper-blade overturned five attack bikes, its backswing tracing a lethal path toward the dismounted White Scars.
But Jaghatai vaulted from his jetbike, his tulwar deflecting the colossal scythe away from his sons.
"The way you school your sons makes me vomit, Mortarion!"
Jaghatai coiled his powerful frame slightly, then delivered a brutal kick that sent Mortarion staggering backward. In the same motion, his blade found the gap in the Death Guard Primarch's shoulder guard with pinpoint accuracy.
"You are not even fit to be called the Master of the Fourteenth Legion. You might as well abdicate to your rebellious whelp, Typhus!"
"Jaghatai! You blindly loyal, savage of the plains! What right have you to judge me?" Mortarion snarled, his respirator wheezing like a broken forge-bellows. "Do you truly believe invoking Typhus will break my focus? How naive. Even the Chaos Gods are mere pieces on a board to me. And I am the one who commands the game."
"I will prove you all wrong. Victory belongs to me alone!"
Mortarion lunged, but in his unsteady footing, his plague-spitter drifted toward the Keshig who were systematically executing the remaining Deathshroud. The Khan's tulwar lashed upward in a vicious arc. The strike did not merely sever the weapon's supply feed; it carved a deep, jagged gouge across Mortarion's breastplate.
"Look at these maggots, Mortarion! You have thrown even the lowest warrior's honor into a cesspit!"
The scythe whipped back from an impossible angle, throwing sparks off Jaghatai's ornate chestplate. But the Khan had anticipated the underhanded strike; his left hand clamped onto the haft of Silence, the Warp-born rot hissing and eating away at his auramite gauntlet.
An oversized weapon possessed inescapable flaws in close-quarters combat.
The gleaming dao swept horizontally, aimed straight for Mortarion's neck.
Six Deathshroud threw themselves forward in a frenzy. One used his bulk to shove both Primarchs apart, while the others brought their manreapers down toward Jaghatai. The Khan drew his blade back, decapitating two of the rotting sentinels in a single fluid motion, while the remaining Deathshroud were rammed and scattered by the heavy prows of the Keshig jetbikes.
Nearby, a Sorcerer of the Death Guard began channeling an unnatural, sickening light. The dark powers of the Warp enveloped Mortarion, pulling his form into the Empyrean.
Yet, just as Mortarion's form began to dissolve into the void, Jaghatai's voice reached him with crystal clarity:
"You never listened to the Father's counsel. In that, your sons are exactly like you."