Some of the Death Guard's ten-thousand-battle veterans who followed Primarch Mortarion were growing dissatisfied with Typhus's attitude. Even if you resent your gene-father, it doesn't change the fact—he is our Legion's gene-sire; we are all his genetic offspring.
"What kind of gene-father is he? Does a gene-father like that even count? Since the Great Crusade he's been a spineless fool.
Only Lord Typhus can lead the Death Guard. We are devotees of Nurgle; it's Nurgle who granted us power!
Mortarion, you're just a Daemon Prince, one more Daemon Prince among the Legion's ranks—there are plenty, even among mortals who ascended after corruption.
But Lord Typhus is different. He is Nurgle's chosen." Another Death Guard trooper spoke up.
A foul reek seeped from him; countless flies and loathsome insects buzzed around the Space Marines, unnoticed—merely another of Nurgle's blessings.
The Death Guard differ from other Chaos Astartes: they maintain immaculate operating theaters, able to perform all manner of Astartes augmentation procedures.
They possess their own sterile laboratories; even the newest Astartes biotech mastered by the Imperium—they've acquired it too!
The Death Guard's numbers are the only ones to rival the Black Legion's, thanks to Lord Typhus's plotting and development!
Thus, the Chaos Space Marines who have joined the Death Guard over the past ten millennia revere this true master of the Legion. As for the gene-primarch—sorry, who is that again? We don't know him. Even some ten-thousand-battle veterans had now taken their place at the side of their former company captain—now, the true Legion Master—Typhus.
"It seems ten thousand years have dulled your memory of my might—of a primarch's power. You think a few petty tricks can oppose a primarch?" Mortarion snorted coldly.
Having accepted Nurgle's task, stepping out of his millennia-long shut-in existence to rejoin his Legion, Mortarion had intended to win over his gene-sons by diplomacy—but they refused him any face at all.
"Cut the self-aggrandizing crap, Mortarion. You're trash. I thought so before; I think so now. If you disagree, duel me. I'll show you what power really is," Typhus said.
Once, he would never have dared speak this way to a primarch. Though he despised Mortarion in his heart, a primarch turned Daemon Prince was among the strongest of the strong.
Even Nurgle's Great Unclean One could not match them—that was a gap of dimensions; their combat power was on different planes entirely.
Even as fallen Daemon Princes, primarchs wielded power beyond ordinary Astartes' comprehension.
But now—ever since some ten years ago, when the lesser Chaos god Vashtorr invented a new augmentation—things had changed.
Nurgle acquired a miraculous monster's corpse from the Imperial primarch Rhodes, and after analyzing powers within, all the Great Daemons received an upgrade.
Now they possessed gigantification; their strength was leagues beyond before.
That was Typhus's confidence to act brazen before a primarch. Today, before the entire Legion, he would humiliate Mortarion—grind this primarch under his heel.
Hence, at first meeting, Typhus chose to unleash full firepower at Mortarion—to smash the primarch's prestige.
He wanted every Legionary—whether ten-millennia veteran or newly joined Chaos Astartes—to understand that he, Typhus, was the Death Guard's true ruler, the rightful Legion Master.
"Come then, my former company captain, my former gene-son. I will kill you here.
So you understand: so-called god-chosen, compared to a primarch, are but ants."
Mortarion had no intention of coddling his former captain. If you insist on a fight and provoke me thus, then I'll kill you here.
Besides, this contest was likely permitted by Nurgle. Otherwise, this wouldn't be happening.
Indeed, Nurgle was remotely watching the match with other Great Unclean One.
This was a cross-era battle. Since the lesser Chaos god Vashtorr upgraded gigantification tech, Chaos had strengthened over the last decade.
Yet all Chaos gods tacitly withheld upgrades from their own primarchs. Why?
Because Slaanesh had gone missing—Fulgrim was wandering and lost.
Magnus, who had thrown in with Tzeentch, had in fact been the Emperor's mole all along; he returned to the Imperium bringing troves of daemonological data, even creating a special psychic ritual that could enslave daemons.
As for Khorne's Angron—an empty-headed fool. Rather than a Daemon Prince, he's basically just a Bloodthirster.
Thus, the only rational, army-commanding primarch left was Mortarion under Nurgle!
Frankly, with gigantification tech and Nurgle's methods to upgrade Great Daemons,
the primarchs no longer impressed as they once did. God-chosen were more worthy of Chaos gods' favor. And since Typhus alone had developed the Death Guard these years, making him the new Legion Master was most fitting.
"Come then! Typhus—defeat Mortarion! Let me see whether my investment in you bears fruit," Nurgle said.
The other Great Unclean One cheered. If Nurgle deemed it right, they deemed it right.
On the Death Guard's Plagueworld, Primarch Mortarion and his former first-company captain Typhus squared off, power weapons in hand for a duel.
"I'll make you kneel and beg forgiveness," Typhus said.
"I don't need your apology. I will take your head. No one insults a primarch," Mortarion snorted.
"Hahaha! The age of primarchs is over—you're obsolete," Typhus jeered to the extreme.
On the Plagueworld, in the fetid swamps beneath the Cathedral of Pox, the ground heaved; murky miasma swathed the arena.
Death Guard Chaos Astartes formed a ring—some silent, some snickering, some openly backing Typhus, glaring at Mortarion with malice.
The droning of fly-daemons filled the air, like a blasphemous hymn to Nurgle.
Mortarion slowly raised Silence, his scythe; pus dripped from its corroded metal. His voice was low and cold:
"Typhus, you've betrayed not just me—you've betrayed the entire Legion."
Typhus laughed, maggots spraying from his rotted throat. "Betrayal? No. I simply saw reality—you're a coward who hid in the Eye of Terror for ten thousand years.
You didn't even dare lead your own Legion! I, Typhus, brought the Death Guard to prosperity!"
He lifted the plague scythe—the skull at its tip vomited toxic smog, warping the air with corrosion.
This was Nurgle's blessing. His power scythe was no whit weaker than the primarch's Silence.
"Now I'll prove it—the god-chosen is stronger than a primarch!"
Mortarion didn't waste words. He burst with near-invisible speed; his scythe traced a sickly green arc, aimed at Typhus's head!
Typhus was ready. Tearfall swept across—when the two scythes met, the thunderous impact hurled dozens of Death Guard from their feet.
"That all you got?" Typhus grinned, suddenly pressing forward, actually forcing Mortarion back several steps!
Gasps rose from the Legionaries—Typhus was overpowering a primarch!
Mortarion's gaze sank. He sensed something off. "Your strength… isn't right."
When had his former company captain matched him in raw power—let alone exceeded him?
Against Astartes, a primarch's might was overwhelming—like an adult handling an infant.
But now that infant bore strength equal to his own—Mortarion felt a twinge of disquiet.
Typhus cackled. "Nurgle gave me new power!" His body swelled; armor split; rotten flesh surged. In moments he ballooned to triple size, becoming a sixty-meter plague behemoth.
"Gigantification, Mortarion. That's why you're obsolete!"
The giant Typhus swung his scythe—each blow carried annihilating force. Mortarion was forced to dodge; even parries left his arms numb.
"What's wrong, Mortarion? Where's your arrogance? Where's your primarch pride?"
Typhus roared, slammed a fist down; the ground collapsed; toxins geysered.
Mortarion was flung by the shockwave, crashing through a rotted fortress ruin. Gigantic Typhus showed crushing superiority.
The Legionaries began to cheer. "Lord Typhus! Lord Typhus!"
"A primarch is nothing special!"
"The Death Guard doesn't need a cowardly gene-father!"
From the rubble, Mortarion rose slowly. His armor was damaged, but his eyes were colder.
"You think… this is enough to defeat a primarch?" He drew a long breath; his warp essence began to boil.
"Typhus, you forget—I am no longer mortal!" In a blink, Mortarion's form swelled; rotted wings unfurled; plague energies coiled about him. He transformed into a Daemon Prince over ten meters tall.
The size contrast looked almost absurd—Typhus a sixty-meter horror, Mortarion a winged daemon barely over ten meters.
Seeing the disparity, Mortarion frantically churned his warp power, drawing in the surrounding pestilential miasma. Empowered by the warp, he grew to over thirty meters, a terrifying daemon with vast, decayed pinions.
That was his limit. His gigantified body wasn't fully material—more a construct of warp energy.
The fetid marsh boiled under Mortarion's feet; turbid fumes whirled around him.
He looked up at the mountain-like Typhus; his rotted wings spread.
"You forgot a truth," Mortarion's voice was like the wailing of myriad dead.
"Primarchs never win by size alone. Don't think becoming a beast lets you stand against me."
Typhus loosed a deafening laugh; his rotten fist slammed down. "Show me, old man!"
Mortarion vanished—reappeared behind Typhus. Silence drew a sickly green arc.
The blade bit deep into Typhus's decayed spine; pus geysered like a waterfall.
"That all?" Typhus sneered as he turned. The wound sealed before the eye. "Nurgle granted me undying flesh!"
He swept Tearfall scythe; the colossal stroke raised a bloody gale. Mortarion dodged at speed but still caught the edge; his breastplate corroded into ragged fissures.
Mortarion spread his putrid wings; swarms of flies poured from the seams of his armor, whirling into a plague-storm that blotted the sky.
"You forget who embodies pestilence! I am pestilence."
The flies burrowed into Typhus's flesh, gnawing, breeding, spreading—his huge body began to collapse from within.
But he only laughed harder. "Useless! Every inch of me bears Nurgle's benediction!" His body unleashed a horrific suction; millions of plague fly-daemons were sucked into him, making him stronger.
You claim pestilence—but you are merely a Daemon Prince. I am god-chosen. Typhus raised his scythe to deliver a killing blow to his former gene-father.
The savage strike hacked Mortarion out of his gigantic form, knocking him back into a mere Daemon Prince—shattering the primarch's last shred of pride.
"No—this is impossible! Nurgle—save me!" Mortarion knelt, roaring in disbelief.
He had lost—to his former gene-son!