There is a saying that the world is a vast web, and the slightest movement in one place affects the whole.
But there is another saying that when the sky falls, the tallest people will hold it up.
From a microscopic perspective, the overwhelming majority of living beings—not only humans—will never break through the barriers between parallel worlds before they die. Many may never even travel far from the place where they were born.
The joys and sorrows of one person mean little to another. When disasters occur beyond the bounds of their own lives without affecting them personally, most people mourn briefly, then return to doing whatever they must to survive.
That is even more true when different nations, species, and parallel worlds are involved.
The gods who had been relocated to higher-dimensional universes after the end of the Age of Gods could naturally see the tragedies occurring beyond their own domains.
Chaldea had exhausted every effort to stop Goetia's Incineration of Humanity and save the Human Order of its world. Were their actions worthy of praise? Yes, of course.
But that was precisely the point. Among the many transcendent beings capable of observing parallel worlds, how many had voluntarily stepped forward, much less personally descended in spiritual form to offer assistance?
Take the appearance of the Jewel Master, Zelretch, for example. Had Selene's annexation not encroached upon his interests and threatened the entire universe born from the Swirl of the Root, he might not have intervened even if Goetia had truly completed the Incineration of Humanity and burned away the entirety of human history in this universe.
After all, Goetia had only burned the human history of this one universe and its derivative parallel worlds. He had not burned away human history throughout the entire Type-Moon world, nor did he possess the ability to do so. What he would have destroyed was merely the human species on Earth in one particular universe—Fate/Grand Order—not the entire physical universe.
To put it bluntly, even if Earth here exploded, it would be nothing more than a drop in the ocean of the greater Type-Moon composite world. Where there was birth, there was destruction. New universes and worlds emerged from the Swirl of the Root at every moment.
Of course, all of that was now in the past. Under pressure from an enemy beyond their domain, the parallel universes had united as never before. While resisting the Imperial invasion forces attacking their own worlds, countless unprecedented cross-world allied armies had also been assembled.
They crossed the barriers separating parallel worlds and traveled to the many anchor universes and worlds born from the Swirl of the Root's "primary currents." Because these regions were also the most closely connected to the Swirl of the Root, they had naturally become priority targets for the Imperial Army under Selene's command.
As for the countless "tributary worlds" born from the Swirl of the Root, they would simply have to delay the enemy for as long as possible... It was a desperate choice, an act of cutting off a limb to preserve the body.
Even if every "tributary" were lost, it would merely cause temporary pain and a quantitative weakening. Once the crisis passed, they could soon recover. But if the "primary currents" were completely eroded, even in part, the damage would strike at their very foundation. It would be a qualitative weakening.
This was especially true now that the Swirl of the Root was pouring all its power into supporting the primordial cosmic goddess, Ashtart, in her confrontation with Selene. Every portion of the worlds under its control that became eroded represented a corresponding reduction in the world's ability to suppress Selene.
When the enemy advanced, they retreated. Every step Selene took forward represented a step back for the Swirl of the Root.
Because the Swirl of the Root possessed no direct consciousness, despite its immense scale, its defensive measures were limited. Aside from its most fundamental self-protection mechanism—assimilation—it could only manifest cosmic disasters, discard and recycle worlds that posed risks or were headed toward destruction, or select a life-form as its agent and grant that being the support of heaven, earth, and all creation.
Indeed, in all the long years since intelligent life first appeared, many had coveted the Swirl of the Root. Most who actively came into contact with it were assimilated, but the principle remained the same.
Even without consciousness, the Swirl of the Root could sense the profound malice emanating from Selene, an instinctive revulsion like prey encountering its natural predator.
Let her inside?
That would be no different from releasing rats into a granary!
The Swirl of the Root would not gamble with its own survival. Perhaps the countless parallel worlds born from it could continue to exist, but it itself would undoubtedly be devoured until nothing remained!
The comparison might not have been entirely appropriate, but this was the impression the Swirl of the Root received after truly encountering Selene's main body at close range. The aura of annihilation surrounding her made it clear that this was not the first time she had done such a thing.
And as it happened, the world containing Chaldea's Antarctic headquarters was one of the worlds born from a "primary current" of the Swirl of the Root.
Likewise, visible to the naked eye across the distant horizon, countless Honkai erosion patterns writhed as though alive, flashing with an uncanny luster as they churned wildly. When Selene sounded the horn of Finality from the Final Singularity beyond the world's barrier, the thunder of war drums shattered the music of peace.
The war drums of the Holy Selene Empire immediately followed. They swept first across near-Earth orbit, then across every continental region and oceanic archipelago, until even Antarctica, one of Earth's two poles, could not escape.
Rumble—!
Accompanied by the thunder of artillery, the earth shook and mountains trembled. Inside Chaldea's command room, beneath the shrill blare of alarms, the spherical structure of the simulated global environment model, Chaldeas, glowed a red so deep it was nearly black.
The dim screens reflected the pale faces of Chaldea's assembled staff.
"Are those dragon species?!"
"And fairies too. Forest fairies, lake fairies..."
"According to our scans, the entire planet is under simultaneous attack."
"The enemy is coming from above... from outer space!!!"
"Previously recorded Sangheili have been detected. The invading force contains vast numbers of extraterrestrial life-forms... There are too many species to categorize."
Operating the equipment with a numb expression, one Chaldea staff member revealed a flash of horror in his eyes. "Their tactical movements clearly display military discipline... The masterminds behind the invasion are humans too!"
"Humans?!"
Bang!
"Enough. Humans or not, it is hardly surprising. Selene herself is humanoid, so it is only natural that humans would exist in another realm."
A slender hand clad in a long navy-blue formal glove struck the table. Seated upright in the commander's chair, Da Vinci spoke rapidly. "Their bodies may look the same as ours, but we know nothing about their way of thinking, cultural traditions, or historical development. In all likelihood, they are completely different from us, so do not expect them to show mercy!"
The good news was that Goetia was dead. Lev was dead as well. They had successfully prevented the Incineration of Humanity and restored the Human Order.
The bad news was that an even greater catastrophe had arrived.
As she watched the ferocious war machines descend across every corner of the planet on the screen, even Da Vinci could not help clutching her forehead, overwhelmed by a wave of dizziness.
The scene unfolding before her at that very moment was simply too shocking.
This was not the individual might of King Solomon, the Heroic Spirits, or the gods. This was the overwhelming power of human civilization—the shock of industrial heavy metal embodied in machines of war.
A vast and empty ice field stretched into the distance, flat and boundless all the way to the limits of sight. It should have been a scene of extraordinary beauty.
But the tranquility of this place had already been shattered by war.
Storms surged across the endless ice field as an enormous fissure split open above it. A multitude of supernatural species poured out from the Inner Sea of the Planet—fairies, dragon species, magical beasts... They shrieked and roared as they surged like a tidal wave toward the descending war machines.
Among them, the light of summoned Heroic Spirits flared repeatedly.
Da Vinci knew that these were Heroic Spirits voluntarily descending from the Throne of Heroes. Their magical energy would be supplied by the planet's land and leylines.
Can they hold them back?
At that moment, clack, clack, clack, clack—
Mechanical drive shafts meshed together amid the roar of gears. Rapidly rotating transmission shafts and heavy hydraulic rods displayed the blood-stirring beauty of heavy industry.
Drop pods, assault craft, heavy tanks, automated artillery, Titans of every model...
Clang, clang—!
Beneath the emblem of the Imperial double-headed eagle, formations of Imperial soldiers trampled mercilessly across one of the few regions of Earth that humanity had never developed, turning the pure white snowfield into a filthy wasteland.
The tracks of armored war machines crisscrossed the land, throwing choking smoke and dust into the air. Imperial soldiers roared as beams of light flashed back and forth, shell casings fell, and bolt rounds erupted from their barrels. Power swords crackled with searing arcs of electricity while chainswords emitted bloodthirsty snarls.
Soon, the bitter Antarctic cold would be driven away by heat—heat in the most literal physical sense. Within the dark, polished barrels of steel cannons, coils ignited with scorching radiance. Dark crimson beams appeared within the black muzzles, swelled, and erupted outward.
Then, rumble—!
Like the signal of an attack, one enormous radiant beam followed another. They illuminated the perpetually frozen land like suns rising across the earth. The ground burned beneath them, resembling a churning sea of fiery clouds.
...
Meanwhile, vrrr—!
A portal glittering like a brilliant jewel slowly opened. With the Jewel Master Zelretch opening the path and the Swirl of the Root granting them unrestricted passage, an ancient floating garden filled with Assyrian and Old Babylonian architecture appeared above Chaldea's ring-shaped main structure.
"What is this?!" Mash immediately threw herself against the translucent observation window, disbelief covering her young face. Was this truly the Chaldea she knew?
After a long moment, Mash abruptly covered her mouth and nose, dropped to her knees, and began retching.
"Is this... an army? A mixed army of humans, intelligent machines, and alien species?" Waver's face turned grim as he stared with widened eyes.
Metal and flame filled everything within sight. The landscape had become scorched earth. Mountains once buried beneath white snow had been stripped bare, while even avalanches had melted away. One enormous crater after another bore witness to the devastation they had endured.
The flames had evaporated every trace of snow and ice, exposing the frozen soil beneath. Corpses covered the wilderness. Dying creatures raised their heads and wailed. Cornered beasts roared. A dragon's chest had been blasted open, its broken white bones and torn flesh exposed to the sky. Wolves had been hacked in half at the waist. Tigers lay decapitated...
Towering warriors in heavy armor and perfectly disciplined soldiers followed close behind, steadily compressing the counterattack from the Inner Sea of the Planet.
Bloodied heads hung from their waists, forming a ghastly sight.
The earth was torn apart by mountain-sized Titans. All resistance was trampled into the mud. Chainswords freshly pulled from corpses had their teeth drenched in blood, making them even more terrifying weapons.
"Astartes and Royal Guards."
As participants in the Romanian Holy Grail War, Avicebron and Semiramis recognized some of them. Having once fought against and alongside Selene, they were all too familiar with these forces.
"Astartes?"
Faced with Waver's confusion, Semiramis flicked a finger. Several enormous screens appeared inside the throne hall. The gold-armored, red-cloaked Royal Guards required no explanation, but the Astartes warriors clad in plain silver-black power armor made her narrow her eyes. Their armor possessed a dark metallic tone, was decorated with only small amounts of gold, and bore alternating yellow-and-black industrial markings.
The emblem of the Astartes Legion appearing this time was a skull-shaped iron mask.
"An unfamiliar insignia. 'Ⅳ'... The Fourth Legion?" It was not one of the three great Legions Selene had summoned during the Romanian Holy Grail War.
In the next instant, boom, boom, boom, rumble—!
The magical shield flashed as the throne hall began trembling violently, creaking under the impact. The Imperial Army, which had been concentrating on annihilating the resistance pouring out of the Inner Sea of the Planet, immediately noticed the Hanging Gardens halfway through emerging from the portal.
In the blink of an eye, artillery fire converged upon it from every direction. Flashes from the magical shield repeatedly illuminated the open dome above the throne hall.
Almost instantly, the Hanging Gardens' defensive spell constructs, the Stelae, began failing one after another as their shields overloaded. Another shot struck immediately afterward. The Hanging Gardens erupted in a massive explosion, trailing thick black smoke as it tilted downward.
"Master, remaining in the sky will only make us a target. There is only one option now. I will land the gardens between Chaldea and the entrance to the Inner Sea of the Planet."
Semiramis spread both hands. Magical crests for controlling the gardens materialized in the air. In an instant, the Hanging Gardens accelerated downward and crashed into the already half-collapsed main structure of Chaldea's headquarters.
Rumble!
Crash...
"Cough, cough... Get outside first..."
Amid clouds of dust and flying gravel, Ritsuka Fujimaru ran out of the fallen Hanging Gardens. Looking upon Chaldea, now reduced to ruins, he desperately wanted to find Da Vinci. Suddenly, a series of tremors struck, making him stumble.
"That direction leads to the Coffin storage chamber! Da Vinci must be there. We have to hurry!"
But the moment they turned the corner, they were confronted by an overwhelmingly oppressive wall of metal.
Bang! Bang, bang!
"Dodge!!"
The black and white twin blades flew from their wielder's hands and collided head-on with the incoming accelerated projectiles. Explosions instantly erupted throughout the corridor.
"Hm? Was this area not already swept once? Why are there still enemies here? Did they descend from that floating fortress?"
"Weren't there supposed to be only a few old, weak, sickly, and comatose invalids left near the storage chamber? How did they cause such a commotion? Go take a look. Finish cleaning them out!"
A squad of steel giants stood at the opposite end of the corridor. Their leader carried a long-handled power axe.
"Da Vinci!" At that moment, Ritsuka Fujimaru no longer cared about the pain from his injuries, because the person hanging unconscious and near death in the enemy's hand was unmistakably Da Vinci.
"Annihilate them!"
With a thunderous roar, the leader swung his power axe at the group in the corridor. "Take their heads and present them to Our Empress!"
Bang! Bang, bang!