Nyx had agonised over this. He had rehearsed it countless times in his head. Now, at last, he stood before Mortarion's door.
...What do I say?
...No more words. Just get it over with quickly.
...No, Mortarion can't be that heartless. I've only ever heard of the 'tragic tangerine duck' — not the 'tragic brother‑killer'.
His internal theatre kicked into gear once more. His Primarch‑level cognition raced through every possible scenario.
One hundred days of father‑son kindness — surely that counts for something, Mortarion!
Brother, brother — don't you miss the happy times we spent together...
(Mortarion: I'll kill you, you bastard!)
Nyx shuddered. He had just 'died' again in his simulation. Though defeating Mortarion was a complete fantasy given his currently recovered state, he felt... well... he probably did feel a little guilty.
In short, a beating was inevitable. He just hoped this good brother would be gentle.
KNOCK. KNOCK.
Nyx knocked softly. Soon, Mortarion's voice came from within:
"Enter, Father."
Nyx heard the word 'father' land with particular emphasis. He smiled wryly to himself. The last vestige of false hope evaporated — Mortarion knew everything.
...Well. May as well face death with dignity.
He pushed open the door, walked in, and sat down opposite Mortarion, as though he were at home.
"What is it, Father? You seem... nervous?"
"We haven't seen each other in days, by the way."
"This time, you come in and don't even call me 'son'."
Mortarion stared directly into Nyx's eyes. An invisible pressure filled the air.
"Ah... Well, lately I've been busy preparing weapons for the Reapers, researching food supplies..."
"So I've been a bit short on time. But—"
Nyx changed tack. He reached into the void; a pocket dimension opened. "I prepared a gift — especially for you."
Within lay a newly forged great scythe. The material was Nostraman adamantium. Though it could not compare to Mortarion's later‑generation Manreaper, it was still a weapon worthy of a god.
Mortarion took it in silence. His fingers traced the cold scythe‑blade. His expression was unreadable.
...Nyx. What are you doing?!
Why did you subconsciously pull this thing out? Because you don't have a skilled enough executioner to chop yourself up?!
"...Father. Or rather, my brother. Nyx."
Mortarion's voice dropped. "Why did you tell me this?"
"When I tried to respect you, to bury everything in my heart — you do this. It makes me just want to—"
"DIE!!"
A cold flash of scythe‑blade suddenly erupted — stopping a mere inch before Nyx's groin! The strike came too fast. Nyx was drenched in cold sweat. Had he not dodged in time, his brother might have sterilised him.
Nyx knew: this time, he was in for it. He simply turned and fled toward the mountains of the xenos overlord.
Oh no — I forgot! I mixed a bunch of 'One Sea Tiger' content into the 'Book of Universal Governance' I gave Mortarion! And I rewrote the fable of Og the Hell‑Warrior!
Only now did he realise: though Mortarion's blows had not been delivered at full strength, he had already begun to mature as a strongman. Today might truly end... badly.
To prevent the Reaper camp from being destroyed in their conflict, Nyx and Mortarion carefully distanced themselves from the area.
Atop the mountain — within the xenos overlord's castle.
The overlord, reclining amidst his accumulated corpses, had just awakened. His daily plan: morning. Though it was already nearly noon, this was simply his breakfast time.
He entered the hall, as was his custom, and awaited his servants to present the day's human slaves for his pleasure.
BOOM——!
The wall suddenly collapsed!
Nyx burst in first. Mortarion followed, scythe swinging. Along the way, any xenos unfortunate enough to merely cross the trajectory of these two were blasted into flying meat paste. Those lucky enough not to die were caught in the rolling scythe‑blade and utterly annihilated.
"Hah? Two humans dare to invade my castle and slaughter my minions—"
"Let me just—"
Before the xenos overlord could finish, Nyx's fist smashed down with wind and thunder!
"Who asked you to speak? Don't interrupt!"
Staring at the rapidly enlarging fist before him, the xenos overlord just managed to squeeze out one last sentence before he died:
"DON'T COME NEAR ME!!"
The xenos overlord's remains had not yet hit the ground when the battle‑scythe's shriek rent the air once more.
Mortarion gave Nyx no chance to catch his breath. The great scythe transformed into a silver‑grey storm of death, sweeping up the dust and blood that now filled the castle, hurtling toward Nyx. His movements were savage, leaving no room for contest. Each strike aimed to dismember and decapitate.
Nyx dropped low, his figure leaning back. The scythe‑blade grazed his breastplate, sending a blinding shower of sparks.
"Mortarion — listen to my explanation—"
He tried to speak, but his voice was cut off by another powerful vertical swing. The scythe embedded itself deep in the stone slab where he had stood only a moment ago. Spiderweb cracks instantly spread for several metres.
"Explanation?"
Mortarion's voice issued through his rebreather, laced with accumulated wrath and disappointment. "Explain how you impersonated his voice? Explain how you used his mannerisms to speak those words to me?"
He wrenched the scythe back and swung again, forcing Nyx to leap once more.
Nyx twisted his waist in mid‑air, barely evading the scythe. He landed on the far end of a discarded long table, raised a hand to wipe the blood from his cheek — nicked by the blade's wake.
"I never intended to toy with you, brother."
"...Well. I may have had some playful intentions at the start. But I never planned for it to develop like this."
"LIES!"
Mortarion roared. His massive frame shot forward with impossible speed, suddenly closing the distance. This was no longer a simple strike — the spike at the scythe's butt end thrust at Nyx's throat like a venomous serpent. The true killing stroke was concealed behind the blade, which had half‑reversed its trajectory. This strike sealed every avenue of escape.
A flicker of helplessness crossed Nyx's eyes. He retreated no further. His left hand suddenly shot out, golden lightning flaring around his fist as it met the great scythe head‑on.
The clash of adamantium produced a dull, thunderous boom. Mortarion's inexorable strike was arrested by this desperate parry. They strained against each other; the heavy tiles beneath their feet fractured inch by inch.
"I admit — concealing my identity was my fault."
Nyx met the blazing eyes behind the rebreather. His voice dropped. "But when I called you 'son'... it wasn't all pretence."
"You DARE speak of that?!"
Mortarion's breathing, behind the rebreather, hitched for a moment. The next second, an even more savage strength erupted from him! He actually abandoned his great scythe — just as before — and lunged at Nyx, driving a heavy‑gauntleted fist into him.
"Nngh—!"
Sharp pain forced a grunt from Nyx. His stance broke. Mortarion seized the moment, mounted him, and snatched up the fallen scythe. The blade rose from below, coming to rest against Nyx's jaw.
This sequence of brutal, close‑quarters combat had completely abandoned the Primarchs' superior martial skills. Instead, it carried the near‑instinctive savagery and harshness of Barbarus — the struggle for survival in a swamp of death.
Nyx finally stopped evading and blocking. Golden current coursed through his entire body — a highly condensed electromagnetic field. The pressing scythe‑blade seemed to encounter viscous gelatine; its speed plummeted. He seized the opportunity, grabbing Mortarion's wrist with one hand while pressing his other hand against Mortarion's pauldron. A surge of majestic force erupted, lifting Mortarion and hurling him back!
BOOM!
Stone columns cracked. Dust rained from the dome. Mortarion rose from the rubble, his steps slightly slowed — yet the fire of battle in his eyes had not dimmed in the least.
"Yes — just like this!"
He rasped, shaking his head to clear the gravel from his pauldron. "Fight me with everything you've got!"