"Let's assume the 'world' is a giant circle."
Three figures stood in the room.
One was the old gentleman who had just spoken. Another was a young man dressed like a mage. The third was a brown-skinned youth in dark ceremonial robes.
"Within that circle exist multiple worlds—Heaven and Hell from the Bible, the World Tree Yggdrasil of Norse mythology, Olympus from Greek lore, and so on. The space between these circles is the Dimensional Gap."
The old gentleman drawing a large circle on a sheet of paper. Inside it, he sketched smaller circles—some isolated, others overlapping, varying in size and shape.
"But the world we came from is a different circle altogether, you can move from the Underworld to Heaven if you have the means—it's within the same circle, naturally. The Dimensional Gap acts like a sea connecting them. However, our world and this one are fundamentally different diagrams. The distance is less like crossing nations and more like traversing planets. That's why free travel between them is impossible—except for a few exceptions."
The mage-like youth, Georg, leaned forward. "One such exception is the summoning of Heroic Spirits via the Holy Grail, correct?"
"Exactly, it's like a radio signal sent to aliens being picked up by chance. If this world—this cosmology—had a 'Throne of Heroes,' things might be different. But with gods still existing in modern times, the balance between mystery and Human Order here is vague and distorted. That's just my perspective as an outsider, though."
To someone from a world where the Age of Gods ended and the Human Order was established, this world's approach to mystery feels contradictory. Yet, to its inhabitants, it holds together. The density of mystery in this world is far greater than in their own. A mage from their world would likely seek ways to cross over upon learning of this one.
"But, Professor, it's unlikely this world could create something akin to Goetia's Holy Grail. I haven't seen the real thing, but after witnessing the Temple of Time…"
"You can create alternate spaces too, can't you?"
"It's not the same."
Goetia's Reality Marble, the Temple of Time—its second Noble Phantasm, Ars Paulina. A workshop in an imaginary number space isolated from time, a miniature model of the universe.
The moment Georg stepped into it, he nearly lost his mind.
His Longinus, Dimension Lost, is the strongest barrier-type Sacred Gear, capable of destroying a nation. Its Balance Breaker, Utopia of Mist, creates an even stronger barrier space. But the Temple of Time was beyond comparison—different in dimension, nature, level, and stage.
It made Georg realize how narrow his achievements and skills were. He recovered only because his intellectual curiosity and scholarly spirit outweighed his sense of defeat. For better or worse, he was a mage and a scholar.
"Have I piqued your interest, Apophis-kun?"
The youth in dark robes was none other than Apophis, a prime Evil Dragon from Egyptian mythology, said to govern solar eclipses—the Primordial Dark Dragon. Revived by Valerie's Holy Grail, he was one of the summoned monstrosities.
"Of course, it's fascinating, our condition for aiding this plan is to challenge another world and its unknown heroes."
Evil Dragons—destroyed dragons, monstrosities driven by destructive impulses and self-destructive desires. The most abhorrent of monsters.
"The world the King of Men seeks to create has no place for us. We're not even allowed to desire it. It feels like our existence is denied. But if we're invited to a new playground, that's another story. Azi Dahaka, Grendel, Ladon, Nidhogg—they all agree with the plan… though Crom Cruach seems to be chasing a different vision."
"Wanting to go to that world, knowing there are multiple beings like Goetia? You're quite mad."
"I'm honored by the compliment, Professor."
The old gentleman meant it as sarcasm, but it didn't land. Naturally—Apophis was an Evil Dragon, a creature whose screws were said to be entirely loose.
"Challenging another world, I've learned something new about 'worlds.' Want to hear it?"
"Oh? Intriguing. Do tell."
"I investigated the space between these giant circles, we need to find a way for them to return, after all. It turns out there aren't just two worlds. If we call this world 'D' and mine 'F,' there's also a world 'E'—a world with a vastly different worldline from both ours and this one."
As he pondered the shocking information mentioned by him, a commotion erupted nearby—gunshots rang out. Bracing for combat, Georg realized the truth upon hearing a voice.
"What!?"
"Stop, Leonardo! Cavities are a dangerous disease! They need immediate treatment! Modern methods only require minimal drilling! So stop! I said stop!"
"…"
In short, it was a child resisting treatment. The issue wasn't the patient, but the one administering it.
"…I'll go save Leonardo before all his teeth are ground down."
"Don't become the mummy you're trying to save!"
Georg faced a deadly ordeal before the battle.
The attack on Azazel, Governor-General of the Fallen Angels, and Tannin, an Ultimate-Class Devil, by a mysterious knightly order spread like wildfire—not just through the Underworld but across all mythologies.
Odin, the Norse chief god, visiting the Underworld for a counter-terrorism meeting, naturally received more detailed information than the public.
"Quite a shock."
"Indeed, to think the Fallen Angel Governor and a former Dragon King would be outmatched. Does the Hero Faction of the Khaos Brigade have far greater forces than anticipated?"
Odin shook his head, exasperated. "No. The ones who attacked Azazel, Tannin, and the Red Dragon Emperor kid aren't from the Hero Faction."
"What? What do you mean, Lord Odin?"
The culprits were a group of knights. Most wore full armor, their faces hidden, and didn't declare their names. But three stood out.
One was Irina Shidou, the missing Church warrior who was supposed to carry Excalibur's fragments. The Church had been tracking her, but her trail vanished until the attack—partly due to limited manpower amid the sudden peace treaty.
The other two wielded Clarent and Arondight—cursed swords of regicide and fratricide. The one with Clarent called herself Mordred.
Circumstantial evidence might suggest they were Hero Faction members, descendants or reincarnations of heroes. But Odin flatly denied it.
"To avoid public panic, Sirzechs and Azazel will likely conceal the truth, not that revealing it would change much. I'd do the same."
"Then who are they?"
"I don't know."
Rossweisse shuddered. It wasn't just shock—Odin, the god of wisdom with prophetic foresight, had thrown up his hands.
"Two facts aren't public. One: Ddraig's soul was extracted from the Sacred Gear. Two: Irina Shidou mentioned a 'Lion King,' likely the enemy's leader, referred to as a 'goddess.'"
"Is some mythology pulling strings behind the scenes?"
"That was expected, Hades, Indra, and the like—Hades to harass the Biblical factions, Indra to create warriors through chaos. Ironically, the kids' peace treaty might only spark more conflict."
As a war god who welcomes strong warriors to Valhalla, Odin couldn't entirely dismiss Indra's approach.
"Maybe you'll find your hero, a Valkyrie your age, still a virgin with no boyfriend—aren't you embarrassed?"
"I'm not a virgin by choice!"
"Then seize any chance you get. Guiding heroes to Valhalla is a Valkyrie's true calling."
His mind drifted to his daughter, a Valkyrie he sealed in a fiery mansion as punishment. By some twist of fate, she fell in love with a human hero, a love that ended in tragedy—one of Norse mythology's most famous.
"Lord Odin, there's something I've been wondering…"
"What?"
After a moment's hesitation, she spoke. "Those pillar-shaped monstrosities, the Demon God Pillars. They claim the same names as the Seventy-Two Pillars. The Hero Faction gathers heroic descendants and reincarnations. And the Seventy-Two Pillars are considered part of the Khaos Brigade. So, does that mean the Hero Faction has—"
"A mere Valkyrie shouldn't speak that name lightly in this place, especially not before Satan or Angels."
Odin interrupted, his single eye gleaming with a rare, stern divine authority. But it passed quickly, and he shrugged playfully. "Don't worry. The situation you're imagining likely hasn't happened."
"How can you be so sure, Lord Odin? Given the circumstances…"
"Simple, if his will had revived, the Underworld wouldn't still be standing."
Rossweisse felt a chill as she grasped his meaning.
"He was human, but not a slave to the God of the Bible. Our mythology got caught in the crossfire—a real nuisance."
"Now, what will those kids without a master do? I'd welcome more heroes to Valhalla, but it's starting to feel like a Wild Hunt, if not Ragnarok."
Rossweisse recalled the Wild Hunt—a procession of the dead, said to recruit or herald calamity. Its leader varies—sometimes Odin, or figures like the Pirate of Salvation, the Queen of Victory, or the King of Knights.
"Report from Valac. The Biblical factions seem unaware of the Lion King's threat."
"Supplement from Glasya-Labolas. The Rating Game among young Devils will proceed as planned."
"Directive from Goetia. While they're distracted by festivities, prepare to defeat the Lion King."
"Report from Vassago. The Old Satan faction assassinated Glasya-Labolas' counterfeit successor. Astaroth's counterfeit successor was eliminated by Florence Nightingale. Proxies from their bloodlines were chosen, but neither the 'Kings' nor their peerages pose significant threats."
"Supplement from Kimaris. Gremory's counterfeit successor faces mental strain in her peerage due to the Red Dragon Emperor's weakening. Sitri's counterfeit successor lacks significant firepower."
"Supplement from Ronove. Agares' counterfeit successor has higher firepower than Sitri's peerage but similar composition. Baal's counterfeit successor has an exceptionally strong 'King' and peerage, befitting the top young Devil. However, they're not a significant obstacle to the plan."
"Question from Saleos. Are there no threats among the Angel or Fallen Angel factions?"
"Answer from Leraje. The Fallen Angels have no notable threats beyond their leaders. Among Angels, besides Dulio Gesualdo, former Durandal wielder Vasco Strada, former Excalibur wielder Ewald Cristaldi, and the Child of Miracles, Teodoro Legrenzi, could be threats. However, their current threat level is low."
"Point from Vine. Shouldn't we recruit them, not just Dulio Gesualdo?"
"Denial from Vepar. Further interference with the Church risks information leaks."
"Agreement from Morax. The rushed peace treaty has caused internal conflicts within the Church. Our interference could destabilize the balance of power."
"Request from Furfur. The Hero Faction and Evil Dragons are insufficient to defeat the Lion King. Additional forces are needed."
"Proposal from Allocer. Summoning Heroic Spirits is a sure way to bolster forces. Activate our Holy Grail."
"Rejection from Crocell. Relying further on their aid is unacceptable."
"Agreement from Haagenti. Summoning Heroic Spirits risks bringing in those hostile to us."
"Supplement from Amon. We sought to destroy the Human Order and fought countless Heroic Spirits in the Temple of Time. Having ties with them, further summonings should be avoided."
"Proposal from Zepar. Then let's increase our pawns in this world."