It had mutated.
For some reason, that was all Rias could think about as she lay in bed in her room in the Underworld.
She was finally alone, the bustle as everyone prepared for Eren's imminent attack, giving way to silence.
Eren had the Boosted Gear. Azazel had confirmed it after examining Issei's... corpse.
Ddraig had been extracted.
Similarly, Samael's poison had been in Issei's body and if he had used it on his... his junior, he would have also used it on the missing Dragon God.
Eren had Ophis's power.
Everything was in place, and Eren only had a few days before he couldn't hold on to Ophis's power anymore. He needed to attack soon.
Everyone was on edge, ready for the shoe to drop and the ground to shake.
And Rias?
She was alone in her room, holding a mutated Rook.
Less than a year ago, she had weighed Issei's life against Eren's potential salvation and chose the latter.
A little over a year ago, if she had a mutated Rook, she would have reserved it for the boy on the bench, even if it meant leaving Issei to bleed out.
Now... Now, all Rias Gremory could see were empty brown eyes, once so full of life and joy, staring up at her in accusation.
Issei Hyoudou just seemed to keep paying the price for Rias' kindness.
Koneko had shut herself down once more at the loss of her fellow Rook. Yuuto and Akeno were doing their best to persevere stoically, but Rias knew them well enough to see the cracks. As soon as this was over, they'd collapse like everyone else.
Rias doubted she could have stopped Xenovia from launching her own personal crusade against Eren if she knew where he was, stray or not.
And Asia...
Xenovia was with her and they were with... with Issei's body.
Gasper still didn't know. He had been with Valerie when Issei had been lured out.
Neither did Irina or Ravel, as Rossweiss was keeping them otherwise occupied. They'd be just as devastated, no doubt.
...There'd be no winning that bet with Akeno. A stupid regret but one of many.
Oh. Right. Rias had never asked him about that rare Goku model, had she?
And now she never would.
Little things like that. Small conversations that never happened. Big dreams never achieved.
It all drowned Rias in a numbness that didn't seem real.
Rias needed to tell Issei's parents. They deserved to know. Know that their son was dead. That he had died doing his best. Though he might have been a hopeless pervert, an entire generation of the Underworld looked up to him as a hero.
They deserved to know that Issei Hyoudou, their son, died trying to save tens of millions of lives.
The entire Underworld would mourn once the news got out of the death of Oppai Dragon...
If there was still an Underworld in a few days,
Satans, when had everything gone so wrong?
Issei dead.
Eren, the villain.
And nobody was sure they were going to live to see tomorrow.
What happened to those happy days spent talking on a bench in the middle of the park?
Was this Eren's freedom? Was this what he was chasing?
This was not the freedom Rias dreamed of.
Her freedom had been stolen from her with the death of her Rook. Her friend. Her family.
Eren had taken it.
He had ripped her freedom to live, to be happy, from her.
And for what?
Power?
If Eren had just explained himself, if he had talked and told them what he wanted, Issei could have given him all the power he wanted... If he only gave up on attacking innocent people.
And now that stupid, good-hearted, perverted, honest boy was dead, and all Rias had was regret.
And a mutated Rook.
A knock on the door couldn't tear Rias' eyes from her mutated Piece.
"Rias," Akeno said softly as she poked her head through the door. Her eyes were red-rimmed, but there were no tears. "Something's happening."
"...Eren?"
"I... don't know. The Satans all left in a hurry. Koneko said she felt something."
"...I'll be out in a second."
Akeno left, giving Rias the last moment of silence she'd have for a long while.
Biting her lips to control her trembling hands, Rias carefully set the mutated Rook on her bedside table.
She'd make a proper shrine to Issei later.
It didn't matter that most Kings would have traded half their Evil Pieces for a mutated Piece, allowing them to reincarnate practically anything under the divine level into their peerage.
Rias Gremory would only use that Piece on the one it was meant for.
And it wasn't Eren Yeager.
********
It was practically a taunt, a goading call.
Yet they had to answer.
Everyone of sufficient power or sensitivity in the Underworld felt the threat, the well-up of power, yet only a few even had the qualifications to meet it.
All four Satans felt it, and all four answered, descending on the untamed wilds that comprised the vast majority of the Underworld.
"It is rare for us to receive beings of your status in our little corner of the Underworld," Sirzechs Lucifer greeted their 'guests' with a charming smile as all four Satans landed on one of the innumerable mountains in the area where Agreas currently flew. "To what do we owe the pleasure of your visit?"
By his side, Adjuka Beelzebub kept his face impassive, but the very fact that nobody could sense anything from his magic told everyone present how ready he was for battle if it came to it. Which was rare. If the researcher wasn't actively fighting, he usually didn't care enough about propriety to stop his eternal research and experiments, even if in the face of influential members of other factions.
But the two beings' surprise 'visit' and clear display of hostility by releasing so much power did not allow for even the slightest levity.
Besides the two Super Devils, their comrades stood, their usual shenanigans absent as even Serafall Leviathan watched their guests with a frown.
Falbium Asmodeus's eyes were open, which said everything that needed to be told about his readiness.
"No corner of the Underworld is yours," Hades grunted. "You're all trespassing. Just because I haven't yet cleaned my attic of the bats and crows doesn't mean I won't."
"As always, your... generosity is appreciated, Lord Hades," Sirzechs nodded amiably without a moment of delay. "Is this in regards to the prisoner that has gone missing? I am afraid we do not have any information to help you find your misplaced charge."
Hades had no brows on his skeleton face, but anyone looking at the Lord of the Dead would have felt his displeasure at the devil's words.
The frozen waters of Cocytus were used to house the most dangerous prisoners of every faction, entrusted to Hades and his Grim Reapers to watch over and protect. In recorded history, not one being had ever emerged from those glacial torrents once dipped in the icy water.
Until recently.
It was an open secret that Hades had let Sameal be taken, though he claimed someone had 'broken in.'
Nobody actually believed Hades would allow any living being to wander freely through his domain, sneak into its most secure parts, and abscond with one of his prisoners, at least without him knowing about it and allowing it.
Still, the fact that Samael had been taken at all was a blow to Hades' record and meant that other factions were much less likely to entrust their problematic members to his care.
Was Sirzechs needling of the Lord of the Dead at the loss of reputation wise? In a way, it was.
It was a reminder that for all that Hades was on the Top Ten, so were the current Lucifer and Beelzebub, even if they were lower in ranking. Together, they had a good chance of achieving mutual destruction with the god of the Underworld.
With all four Satans working together, there was a decent possibility that they could kill Hades and only suffer injuries. They didn't want that, but the threat needed to be acknowledged.
For all his power, Hades had never been strong enough to chase the devils and fallen angels out of the Underworld completely, and he would do to remember why.
Unfortunately, Hades wasn't alone in this visit to the Underworld.
"Sameal is back where it belongs," Indra said amiably, not minding the barely concealed hostility he was receiving. "That's not why we're here. We are here to bear witness."
"Lord Indra," Sirzechs' smile was as friendly as ever as he slightly inclined his head to the Hindu god. "I'm afraid we don't have anything worthy of your attention on hand. Certainly nothing that could distract you from your preparations."
If Sirzechs and Adjuka could tie down Hades and all four Satans together could kill him, then what could they do to Indra?
Barely anything.
If all four fought with everything they had, holding nothing back and using their very lives as currency, the most they could hope to buy with their sacrifice was to injure the god slightly.
But, sometimes, that was enough.
Indra could not afford any sort of injury. Not when Shiva was waiting in the wings, ready to tear him down in a moment of weakness.
It was widely known that both sides were gearing up for a battle, possibly of apocalyptic proportions, and one wrong move would spell their doom at the other's hands.
The Satans didn't have to win.
They just had to prove that killing them wouldn't be worth the gains.
That was how you survived in a world filled with those more powerful than you.
You pitted the strong against the strong and ensured you were just enough of a thorn that stepping on you wasn't worth the pain for either side.
"I don't know about that," Indra chuckled. "I'd say the end of an era is worth my time."
"'End of an era?' That's a good subtitle for my next movie," Serafall's smile was wide, friendly and as cold as Cocytus' waters.
"I hope you don't mind that I am more of an Oppai Dragon fan." Indra's words finally drew a reaction from the two Satans who had spoken as their smiles dipped.
Both of these gods seemed to know of Issei Hyoudou's death, even though it had only been a few hours.
Even if one ignored the fact that Sirzechs and Serafall were fond of the boy on a personal level and only thought about the death with the cold calculus of supernatural geopolitics, it was undeniable that the devil faction had just lost a significant source of power in the form of the Red Dragon Emperor.
And now it was in the enemy's hands.
Despite the smiles from both sides, there was no mistaking the current situation.
These two gods, members of the Top Ten, were enemies of the New Satans, thanks to their affiliation with the Chaos Brigade.
"There is so much death in the air," Hades spoke with a hollow laugh. The God of the Dead conjured a throne of bone and reclined, watching the Satans with the arrogance of someone who had all the knowledge. "I am quite curious. Will all the Satan's bats and all the Satan's men manage to kill a human teenager? Or will you all be crushed under the Titan's foot?"
"You'd know about being crushed by Titans, wouldn't you?" Serafall snipped, given that pleasantries had fallen by the wayside. "Way I heard it, he's had you all dancing on strings, even when he was gone."
If Hades cared about the allusion to being eaten by his father, he didn't show it. Instead, it was Indra who spoke, his voice low and serious.
"This battle will be the most important the world has seen since the death of your predecessors." The God of War intoned as he looked up and out at the flying city of Agreas. Almost as if he was speaking a prophecy. Then, the effect was ruined when he grinned wildly. "I wouldn't miss it for the world."
"Battle?" Sirzechs tilted his head curiously. An act that no one bought. "If Lord Indra says there will be one, then I can only agree. If I could just ask, who is going to be fighting?"
"Do not try and ply your tricks, Deceiver," Hades shot down. "Neither of us shall take with your kind today. We do not need to."
"I won't fight today," Indra agreed, also taking a seat, though he just sat on a rock. "Like I said, I'm here to watch."
It was bait.
They all knew it.
But some bait must be bit, no matter how obvious the hook.
"Watch what?"
Indra gave Serafall a smile, glad she had decided to play along.
Then, he cut the mountain range with a swing of his hand.
Plants. Animals. Stone.
It all disappeared where the God of War's hands passed. Eradicated so utterly that not even dust rained down.
In the blink of an eye, where once was an enormous mountain range, wild, untamed, and filled with demonic beasts, was now just a flat stage of stone.
Nobody flinched at the casual remoulding of the geography.
They were each strong and experienced enough to know when power was being used to target them and when it was just being used.
There was a beat of silence.
Then another.
Then another.
It started to get awkward.
Indra sighed.
"Being late for a battle signals lack of preparation."
"No one is more prepared for this battle than me," Cao Cao said, emerging on the flat platform Indra had created from a swirl of mist, his voice easily carrying to the gods and Satans.
As did his aura.
Cao Cao glowed with Light.
Not just from the True Longinus slung over his shoulder casually, the speartip still stained in Loki's blood.
No, his very flesh radiated the holy Light that was anathema to devilkind everywhere.
Just looking at Cao Cao would have been enough to kill newly reincarnated devils.
"Your sense of timing just sucks," Cao Cao told the God of War with a casual smile. "Don't try and match Eren."
Then, with the hand not holding the ultimate Sacred Gear, the leader of the Chaos Brigade tossed something in the air.
It was a casual throw, for all it crossed meters of distance to land in the middle of the gathering with a wet 'Splat.'
Though deformed from its landing, there was no mistaking the shape, smell, and bloody splatter of a recently severed head.
Though it was Hades, rather than the Satans, who identified it.
"Lillith?" The God of the Dead said in surprise. "I had thought her dead for a millennia."
That got the devil's attention as they looked at the severed head in renewed consideration.
It was female; they could tell that much, but so many of its features were distorted and warped that making out specific features was impossible.
Adjuka Beelzebub, of course, identified it within seconds of scanning it.
"It is Lilith," he confirmed. "She has the same genes as every Pure Blood devil, and there is only one communal origin."
Lillith, the first wife of Adam, was the origin of all 72 Pillar Houses. She had the ability to reproduce asexually, and every bloodline ability of the devils could be traced back to her.
But she had disappeared in the years after the death of the original Satans.
"Ancestor will be sad," Sirzechs sighed. That was all the reaction the current Lucifer had to the death of his predecessor's first wife. "She's looked for traces of her mother for years. Where was she?"
"Rizevim had her confined to a lab," Cao Cao said, his smile taking on a malicious glee. "He had no love for his mother and had been trying to get her to spit out Super Devils for centuries. I did her a mercy. Though it is not heroic, I will admit that it felt good. He's been pissing us off for years. Imagining the look on his face when he gets back to his lab..." Cao Cao let out a wistful sigh, then shook his head. "Still, devils like him are the reason I am here."
"If you are opposed to Rizevim, we do not need to be enemies," Sirzechs offered. "No one here is a fan of his either. My wife, in particular, has questions for him."
Even if he had killed the Mother of Devils, Cao Cao was still a young man with enormous potential.
Sirzechs Gremory hated nothing more than seeing youth throw their lives away in war. He had been there. He knew what it was like.
"Do not mistake me, Crimson Devil," Cao Cao levelled his spear at Sirzechs. The weapon thrummed with holy power. "I did it because it served our plan. Now, there will be no more devil bloodlines in the world."
"Do you truly hate our kind so much?"
"No. I am not doing this because I am against devils."
"Then why fight us?" Serafall asked. "You have a bright future ahead of you. Why throw it all away on war and violence?"
"None of you understand," Cao Cao shook his head, smile fading to a look of determination. "I know of you four. I know of the Embodiment of Destruction. I know of the One who Controls Techniques and Laws. I know of the devil who created the Underworld's Arctic and the man whose defence has never been pierced. I know it all."
"Then you know you will die," Falbium Asmodeus spoke for the first time. There was no anger, hatred, or even animosity in his voice. He was just stating facts. "Your current state is unsustainable. Humans can become angels. Humans cannot be angels. Only the Longinus is keeping you whole. If you get treatment, you'll survive. If you use your Gear, you won't. All we have to do is outlast you, and you will die on your own. "
"That's the point," Cao Cao laughed. It was a happy laugh, joyful and free. Like he had no burdens left to carry. "I have no future. I traded it for glory. I traded it for a name that will live on for millennia. That is what it means to be a hero."
"Heroes kill," Sirzechs agreed. "But killers are not heroes. There is no heroics in the slaughter of innocents. Men, women, and children."
"That worry does not belong on this battlefield," Cao Cao shrugged. "That battle is for someone else. Right now, my comrades are fighting their own battles."
Far away, all across the world, the flames of war lit, consuming lives as they burned.
Most were simply a more extreme version of the usual infighting within a pantheon.
'Evil' gods and dragons attacking their 'good' counterparts to upend the status quo and replace who was in charge.
Rogue and heretical magician factions turned upon those 'orthodox' practitioners who had rejected their ambitions.
It was chaos, pure and simple.
But it was organized chaos.
Usually, the forces of evil were not in any way weaker than those of order. Yet, time and again, they had been pushed back.
Defeated, sealed, and marginalized.
Because they could not work together. These beings, selfish, cruel, and ruthless, could not abide by any sort of order. It went against their very being. They usually fell to infighting, cooperation of their enemies or treachery from their 'allies.'
Eren Yeager had changed that.
Crom Cruach's death had cowed them. Ophis' power tempted them. But Loki's death served as a warning that even gods would die if they went against his plan, even without Ophis at hand.
So they listened.
When Eren called them to war, they answered.
Revived by the power of the Grail, Apophis bore down on the lands of Egypt, ready to battle with Aten once more. Behind him, the light of the sun faded.
And were rewarded for it.
Nidhoggr roared as the horde of beasts, conjured by Annihilation Maker, clawed their way from the roots of Yggdrasil to assault Asgard.
For the first time, the agents of chaos worldwide had the support they needed to match their counterparts.
But only to match.
Never to exceed.
A plan only possible for a man who had seen it all. A man who knew exactly what steps he needed to take to reach the end he wanted.
All so the war that engulfed the supernatural world would burn hotter.
But even in the inferno, flames still rose higher than others.
Seigfried pulled Gram free of the final exorcist's corpse. He wasted no time in destroying this lab. He had a dozen more church bases to get to before he moved on to his final battle.
None shone more brightly than those short-lived sparks of humanity.
Jeanne shone with holy light in the darkness of Nyx's magic. Her light was the beacon of her army of heroes, leading them forward toward Olympus.
Fueled by fragments of Infinity, they burst into pyroclastic destruction, determined to carve their mark on the world.
Heracles laughed wildly as he fought side by side with Angra Mainyu and a newly freed Azi Dahaka against the forces of Ahura Mazda.
"They will die, just like me. But each of us has our role to play."
"And your role?" Sirzechs asked sadly. "What is worth all this death and destruction?"
"My role is to be the spear of humanity," Cao Cao said proudly, no longer hiding the murderous intent in his eyes. "I am the first human to kill a god. My very existence is proof of the potential humans hold. But it is not enough. I am going to show the world that even the strongest can die. Today, a human will kill one of the Top Ten."
"You want to kill me," Adjuka said simply, feeling the focus of the intent. "You want to end the Evil Pieces system."
"For too long, humanity has been the toy of the powerful," Cao Cao declared. "Devils, in particular, have taken our best for their own. You are not the only ones, just the most egregious. But that ends today. Today, humanity is no longer the prey."
All over the world, Eren's war burned the ground to ash.
"We are the hunters."
And in the Underworld, the ground began to Rumble.