Some time in the distant future...
Kai Lung, Captain of the Fourth Company of the Devourers Legion, pried the obelisk from the hands of the cold, dead, Necron Lord. He raised it up to the light, its emerald symbols glowing faintly. It was a meter in length, at best, covered in eldritch symbols and wards that baffled the mind. This was it. It couldn't be anything else. Another piece of the puzzle, the twentieth key to the prison of their father – one of one thousand other keys.
Thus far, only twenty had ever been found, scattered as they were around and across the breadth of the Milky Way galaxy, often in places they'd never expect or in the possession of those they'd never suspected. The keys were of Necron technology, however; that much was clear. And so logic dictated that, at least, most of it would be in the possession of the skeletal machines. After all, it had been the Necrons themselves who ambushed and caged their father, unable to defeat and kill him.
The Necron Lord on the ground, alongside its armies of soulless machines, hadn't survived their lightning assault. Its defense was valiant, of course, wounding and injuring a few of his brothers in the brief, but otherwise one-sided battle that ensued the moment they cleaved apart an entrance into its Tomb Complex and attacked with the fury of a living storm. Extreme and overwhelming force almost always worked best against the Necrons, who were powerful, but slow to rouse. Their slumber worked against them.
Approximately twelve were injured – ten of them losing a bunch of limbs or entire sections of their torso. But, no more than that; they lost none of their brothers in the battle.
Sure, a few of them almost died, but that was it.
To become a full-fledged Devourer, their aspirants needed to master the use of Reverse Cursed Energy to heal themselves and each other if necessary. On the battlefield, it made them nearly impossible to kill. It gave them the title of strongest among the legions.
Even now, ten thousand years after the Great Heresy, the Devourers still retained their title as the strongest of all Astartes legions – though a few came close to challenging their record, such as the Ultramarines, who lacked brute force but made up for it through logistical and organizational prowess. All feared them, the Sons of the Cursed King. Certainly, their numbers were far fewer compared to the other legions, due to their rites, their training, and their traditions, but a single one of his brothers was worth a hundred Space Marines; so powerful were they that even their Scouts were powerful enough to give the Sons of the Night Haunter some pause and cause the children of Angron to turn and flee.
After all, not even the Thousand Sons of the Cyclops could claim to have killed a Primarch as their brothers in the Great Heresy had done – their greatest triumph to date, the day their father finally acknowledged them as his own.
Sure, it hadn't been a fair fight, but their father taught them – many times – that those who fought fair were not trying to win. And, more than anything, what mattered was winning. In the end, only the strong remained. And the First-Heretic learned that lesson quickly enough when the first of his brothers, the ancients, cut him apart unto pieces so tiny and so numerous that even his soul was shattered permanently.
Behind him, a hundred Devourers Space Marines stood by, keeping watch over the ruined machines; with Necrons, one never knew when they'd start reanimating themselves. Even the ruined Necron Lord at his feet, torn apart by his Domain Expansion, would eventually wake up. It was simply the way of things. One could not kill those who were already dead.
They should know. Compared to any other Adeptus Astartes legion, the Devourers had the most run-ins and engagements with the ancient, deathless automatons – relics of a bygone era – in their search for the keys. It was a shame, though; they couldn't exactly devour the automatons to gain strength as they could with other foes. And Living Metal was deathly poisonous, even with the aid of Reverse Cursed Energy.
Kai Lung turned and raised the obelisk into the air for his brothers to see. They did not cheer. For theirs was a solemn duty, the single greatest quest and contract the legion has ever taken; and that was the acquisition of the thousand keys necessary to open the prison that held their father. Instead of cheering, his hundred brothers merely stomped their foot on the ground once. "This is the twentieth key, my brothers! Another step closer to freeing our father!"
The stomped the ground once again. Kai Lung breathed in, smiling underneath his helmet. Soon enough, their father would return and make the galaxy tremble. It was a testament to their father's strength that the Necrons themselves intervened and imprisoned him, locked him away in a cage within cages. Their father's prison had three layers – as far as they knew. Ten thousand years of research led them to the conclusion that their Primarch was trapped within something known as a Tesseract Vault, which itself was kept within a Tesseract Labyrinth, and finally within a Star Chamber, an indestructible prison that was powered by the combined essences of no less than ten Transcendent C'tan Shards, acting as batteries.
Such a prison, his forebears said, would've been enough to capture a god for an eternity. But, even now, Kai Lung knew, his father – the father of all Devourers – fought against his chains. For wherever they went, the Devourers felt the presence of their progenitor, the greatest and most powerful of the Primarchs, Ryomen Sukuna, King of Curses, Demon Eater, World Drinker, and World Breaker.
At his feet, the Necron Lord twitched. Scowling, Kai Lung sent forth a single Cleave, cutting down the soulless automaton once again. "Let us depart, my brothers."
One of his brothers stepped forward, carrying a jet-black container that was meant to keep the twentieth key safe and hidden. It snapped open, hissing. Kai Lung then placed the key inside and closed it. The container vanished in a flash of black, now safely tucked away in the armory of their Battlebarge. "Brother Munisai, it is time."
Another one of his subordinates stepped forward as Kai Lung joined the ranks. Brother Munisai, their Company Librarian, raised a gnarled, wooden staff in the air. Time and space rippled around them, matter and energy condensing and reforming. And then, Brother Munisai slammed his staff onto the ground as he chanted, "Cursed Technique, Lapse: Omnipresence."
And then, in the blink of an eye, the entirety of the Fourth Company of the Devourers Legion disappeared, reappearing back in their vessel, the Endless Gullet. "Good work, brother."
The search for the thousand keys never stopped, Kai Lung thought. Their next destination was world overrun by the Tyranid Swarm, rumored to house another key. It would by a buffet for himself and his brothers. If he had to choose one foe he enjoyed fighting the most, it had to be the Tyranids, simply because the hungering alien hordes, quite simply, had nothing that could truly hurt them or, at least, put them down for good, while he and his brothers were free to feast on the fallen aliens, gaining strength from their corpses.
It would be fun.
- Back to the present -
It had taken them a full year, but – eventually – his flock, his people, were able to cleanse the planet of any stray or remnant machines. He also learned that there were far more humans beneath the surface than he'd expected. And that the initial group he met, led by the human who called himself the Preacher, apparently wasn't the first to foresee and anticipate his arrival – many of them immediately falling to their knees in worship at the mere sight of him, their fervent faith fueling his power. By the end of it, the only humans left were those who worshiped and adored him. Or, more specifically, the only ones who ventured out onto the surface were his humans. There were a few other 'tribes' that opted to live even deeper underground, fleeing and retreating into the shadows in places so distant and so deep that Sukuna couldn't even sense them anymore.
He'd pay them a visit eventually. After all, it'd been so long since he last ate humans and he might as well eat the ones that offered him no tangible benefit. But, he figured, he may as well just allow them to flourish for as long as they feasibly could – the more the merrier, after all. He wanted a feast, not a quick lunch. And, ultimately, he had the luxury of being able to wait. But now, Sukuna found himself in yet another situation that he was woefully unprepared for – ruling.
With the planet secured and conquered, it was now time for the part that he dreaded, but ultimately and reluctantly accepted, which was actually leading his people. And this was an entirely different beast from simply leading them in battle. No, this was administration and management, two things Sukuna would readily admit to having absolutely no experience in. But, ultimately, how difficult could it actually be? There were two things he had to keep in mind. Humans were fond of rituals; these ones, in particular, worshiped him already and so teaching them a few rituals and rites, practices to cement their faith in him and to remind them everyday, would greatly improve the constant Cursed Energy output he received from them. Another thing was that humans needed food, water, and shelter.
Shelter was easy. One of the Cursed Techniques he'd stolen from a now-diseased Jujutsu Sorcerer allowed him to manipulate rock, stone, and soil – not useful in combat, which was why he'd never really bothered with it much. But now, it finally found some use. And so, with it Sukuna built castles, made entirely of condensed stone, mostly impervious to harm, each one large and spacious enough to house thousands of people. How they decorated and furnished the interiors was up to them. He was here to cultivate their faith, not treat them like infants.
The food and water part were much harder. The waters on the surface of the planet were... poisonous. One sip was all it took to reduce a grown man into a petrified husk. Food... simply didn't exist, either.
Luckily, the Preacher had... something of a solution. Apparently, their ancestors, the original humans who came to this world, seeking to build a better life for themselves away from Earth – a concept Sukuna still had trouble wrapping his mind around – had brought with them a great many things to help them cultivate farms, raise animals and other livestock, and purify water. All of these things, he said, were kept in the Deep Vaults, deep beneath the Earth, hidden and protected so that those who came after them would have a fighting chance at similarly building a life for themselves.
What they hadn't expected was for their descendants to devolve into warring tribes of unwashed barbarians.
"The solution seems simple enough, then," Sukuna said, putting the Preacher in charge, because he couldn't really be bothered with all the nitty gritty things, could he? "We're going down there and we're not climbing back out until we have everything we need to build an actual civilization. Is that clear?"
"Of course, great one," The Preacher answered, lowering his head in reverence.
Sukuna eyed him for a moment, before nodding. "Take as many or as little people as you need. They are allowed to sacrifice their lives if necessary, but it's better if they lived; what's important is these materials you spoke of are found and brought back."
"As you command, great one."
And so, the Preacher and others like himself, gathered more or less most of his flock, forming three groups, each one searching for these artifacts – one to look for seeds, another to look for the time-locked animal eggs for livestock, and the last one to search for the water purifier.
Sukuna remained upon the surface, guarding those who did not venture back into the tunnels – the sickly and the elderly, women and children. If they weren't so reverent of him, then the King of Curses would've eaten them already. As it was, Sukuna found himself tolerating their presence; plus, really, the humans didn't bother him too much. A week later, the expeditions returned with good news.