Within the fictitious history of Busalet, in a desert valley within the nonexistent borders of that lost kingdom, a tall building stood towering amidst the windswept sands.

This structure once belonged to a wealthy merchant. Back when the valley functioned as a mining site, the merchant who had purchased the mining rights constructed this large residence for himself. After the minerals were exhausted, the place was left idle—until half a year ago, when someone bought it anew.

Now, the building nestled in the valley stood intact and clean. People in robes of various kinds passed through its halls from time to time. Camels loaded with large sacks fed from troughs at the gate—clearly used for transporting supplies. All signs indicated that this was a site of long-term human habitation.

Deep within the tall building, in a spacious, windowless chamber illuminated by an unusual brightness, Vania knelt upon a complex ritual array. She was dressed in simple white garments, her eyes tightly shut, breathing heavily, drenched in sweat. Her exposed skin was covered in rashes.

Wearing a pained expression, Vania activated both the altar and her own power to heal herself. Within a gentle halo of golden light, the suffering etched on her face gradually eased, and the rashes slowly began to fade.

“Haa... haa... How was it, Miss Dorothea? What were the results this time?”

Vania asked between deep, labored breaths, wiping sweat from her face as she looked toward Dorothy, who was seated at a nearby lab bench. Clad in a white coat and wearing glasses, Dorothy turned toward her and replied.

“Very good... This mutation has already enhanced all the traits we needed. We’ve just about met our expectations.”

As she spoke, Dorothy removed her glasses and looked at Vania with a solemn smile.

“All the data meets the requirements. This experiment is complete. The next step is to return to reality.”

“Is that so... it’s finally... finally finished. That means everyone can finally be saved...”

Upon hearing this, the weakened Vania exhaled a long breath and her face lit up with a joyous smile. The heavy weight in her heart seemed to finally lift.

“Yes... You’ve worked hard during this period, Vania. Thank you.”

Dorothy spoke earnestly, and Vania shook her head and responded.

“It’s what I should do. If anyone should be grateful, it’s me thanking you, Miss Dorothea—for giving me the chance to save so many lives. If I had to watch so many people die in agony from cult-related illness and do nothing, I fear I would’ve lived in shadow forever... It was the great Aka, and you, who gave me this chance...

“And Sister Ivy too... If not for the altar and equipment she provided, I doubt I’d have made it this far. The Radiance Church has also supported me every step of the way...”

Vania spoke seriously, and Dorothy waved a hand dismissively and replied.

“All right... No need for more words now. Go get some proper rest. Once you’ve recovered, we’ll go out together—return to the ‘real world’ and confront that monster, that plague... once again.”

“Mm!” Vania nodded firmly from within the ritual circle.

…

In the blackened night of Busalet’s wasteland, the battle of biology versus steel, searing flame against corruption, destruction against regeneration, still raged on. After Dorothy and Vania departed, Ivy remained alone in the real history, piloting her steel vessel and continuing the bombardment against Amuyaba.

At this moment, Ivy hovered about 1,500 meters above ground. Below her stretched an expanse of green cloud. Over time, the mutated bacteria released by Amuyaba—the rust iron spores—had grown to staggering levels. What began as a factory-level pollutant had now reached meteorological-scale fog. The massive cloud of green spores pressed down upon the land and steadily rose skyward, gradually climbing toward Ivy’s altitude. Looking down from her vessel, she saw a vast sea of clouds made of spores—the creeping tide giving her a pressing sense of urgency.

Now about 400–500 meters above the spore cloud layer, Ivy fended off an increasing number of chitinous arrows and flying explosive bugs with her close-in defense system, while continuing to unleash energy barrages downward to suppress the fully monstrous Amuyaba.

Her translucent avatar floated above the gothic spire of her bridge, sternly watching the spore cloud sea below. The mounting pressure from anti-air fire and the rising fog threatened to overwhelm her.

She could have flown higher to reduce the pressure, but that would’ve compromised her suppression of Amuyaba.

Vania’s departure had left Ivy’s temple-grade ritual site without a presiding host, which meant she lost access to a wide-range lifeform detection radar. Though she still had a strong spirituality-based radar, it was only sensitive to spiritual reactions—not specialized in tracking living organisms.

The region around Amuyaba was saturated with spiritually active spores, flooding her sensors. Everywhere she scanned, spirituality reacted in such abundance that she couldn’t distinguish anything.

If she flew too high, her radar would just return a field of noise—blips of undifferentiated spiritual response. At her current altitude—just under 2,000 meters—she could still make close-proximity assessments to spot denser concentrations of spirituality and roughly determine Amuyaba’s location for targeting.

But this also placed her within range of Amuyaba’s increasingly intense counterattacks, and she was beginning to falter.

“Just a few more minutes... it’s almost time...”

Ivy murmured grimly, watching the intensifying assault below. She silently recalled the moment Dorothy and Vania left her, telling her of a certain time they would return—bringing with them the key to ending this nightmare.

Even while holding the line, Ivy wasn’t relying solely on her secondary guns. The prow of her vessel had opened again, revealing the massive barrel of the primary cannon mounted along the ship’s axis. The cannon now glowed brightly, charging for a devastating shot.

The power of this main cannon was tremendous—enough to annihilate most of Amuyaba in one shot. But because Amuyaba’s regenerative abilities were powered by immense spiritual supply, even the slightest remnant would trigger rapid regeneration. So one blast alone wasn’t enough. Victory still hinged on the return of Dorothy and Vania.

As Ivy charged her cannon and maintained suppression, her spiritual radar suddenly detected a concentrated spiritual signature—the core body of Amuyaba—beginning to move rapidly within the spore cloud, rising from the depths toward the surface, as if suddenly taking flight.

“What...?”

Just as she voiced her surprise, the sea of spores below tore open—an enormous entity burst forth from within.

A giant flying insect.

A brownish-yellow chitinous shell covered the entire body. It was tens of meters long, with two pairs of thin, translucent, web-veined wings on its back flapping rapidly. Its massive body stretched over 150 meters, ending in a swollen, sac-like abdomen riddled with countless holes—so densely packed they triggered a visceral revulsion in anyone with trypophobia. From these holes, countless winged spawn burst forth, and clouds of spore mist sprayed out.

The insect's long body bore several pairs of limbs near the front. The foremost pair were gigantic pincers over 30 to 40 meters in length, shaped like mantis scythes with serrated edges—grotesquely exaggerated weapons made of hardened chitin. And at the very front of the insect, a twisted, giant human face protruded—bearing Amuyaba’s hideous and contorted visage.

While hiding within the spore fog, Amuyaba had endured Ivy’s bombardment, undergoing massive growth and mutation—transforming its main body into a colossal flying insect and now launching a direct aerial assault against Ivy.

“Fall, you steel bitch!”

Seething with rage and resentment, Amuyaba—now in its insect form—swung its enormous scythe-like pincers at Ivy’s hull. While her close-in defense systems handled flying spawn and chitinous arrows decently, they were completely ineffective against a monster of this size. The system’s small-caliber guns and flamethrowers were useless against Amuyaba’s armored shell.

Fortunately, the moment Ivy detected Amuyaba approaching, she had already started maneuvering. Before the scythes could land a hit, she activated her numerous propulsion nozzles—previously dormant—blasting out intense flames. These nozzles, positioned at her stern and along both flanks, boosted the already floating vessel—suspended by some powerful mystical anti-gravity mechanism—pushing it swiftly to safety and evading the strike, pulling distance between her and Amuyaba.

Once at a safe range, Ivy turned her countless gunports toward Amuyaba and unleashed a barrage. Since Amuyaba had emerged from the fog, Ivy included a large number of solid shells in the salvo. But as soon as Ivy fired, the many flying spawn around Amuyaba began self-destructing, and spore clouds gushed violently from its body’s holes—once again shrouding it in mist.

With the spore mist obscuring the view, Ivy’s solid shells became useless again. Only a few energy rounds penetrated the fog to strike Amuyaba, but the damage was minimal—and Amuyaba regenerated quickly. It charged again, forcing Ivy to boost her thrusters to dodge.

Thus began a relentless pursuit—Amuyaba flying while constantly generating spore clouds to cloak itself, all while making aggressive close-range attacks against Ivy.

Against this charging spore cloud swarm, Ivy demonstrated extraordinary maneuverability. Her 400-meter-long airborne dreadnought, more agile than many 200-meter seafaring main vessels, dodged the attacks with complex and sharp movements—responding with counterattacks whenever possible. Many of her maneuvers were so extreme that if her frame were made of ordinary steel, it would've broken apart long ago.

In this way, the two colossal entities—both over 100 meters long and weighing tens of thousands of tons—engaged in fierce, close-quarters dogfighting in midair. It was like an old-fashioned dogfight between fighter planes, only on a scale far beyond comprehension.

Throughout this skirmish, Ivy avoided any direct hits. However, when Amuyaba flew close by, its spores scattered onto Ivy’s hull. Despite her ship being made of high-strength mystical metal, parts of it began to show signs of corrosion—marking the first time Ivy had sustained damage in this battle.

Even as her hull began to rust, Ivy wasn’t worried about her condition. What she truly fretted over was her main cannon. Ever since Amuyaba had taken to the air and begun its relentless harassment, Ivy’s main cannon—her axial weapon—became difficult to aim. Fixed along the central axis of her hull, the cannon only fired in the direction her bow faced. It couldn’t pivot like a turret. While ideal against stationary or ground targets, it was ill-suited to track a fast, close-quarters flier like Amuyaba. The cannon was nearly charged—but she couldn’t get a proper aim.

“Such a nuisance...”

Faced with Amuyaba’s shift in tactics, Ivy frowned slightly. While grappling in this intense aerial duel, she also kept track of a precise moment—etched into her internal countdown. That moment was nearly here.

“I hope... you’ve found the means to change everything…”

As the appointed time arrived, Ivy suddenly adjusted her thrusters and shot toward a coordinate in the sky. Tactically, it wasn’t an ideal location—it exposed her to danger. Amuyaba instantly spotted the flaw in her movement.

Without hesitation, Amuyaba charged toward the vulnerable Ivy. Though she narrowly avoided a direct collision, she failed to dodge two explosive bugs it spit at close range. These slammed into her port side and detonated, splashing concentrated green spore fluid across her hull. Corrosion hissed across the metal—secondary turrets on that side ceased functioning, and patches of rust rapidly spread.

“Hah! Got you now, steel bitch!”

Seeing that it had finally inflicted real damage, Amuyaba shouted in glee, jeering midair. But Ivy didn’t even react. She showed no frustration at the weapon loss—only let out a soft breath of relief.

Because at that very moment—precisely at the appointed time and coordinate—Vania, who had vanished inside the ship before, suddenly reappeared within the chapel onboard. She wore her white nun's robes once more, returned at last.

“How’s the situation? Was the experiment successful?”

Ivy’s avatar appeared before her instantly, asking. Vania—whose demeanor now seemed calmer and more mature—steadied herself against a pillar, adjusting to the ship’s high-speed motion, and responded with a gentle smile.

“It went well… We succeeded!”

“The result?” Ivy pressed seriously.

“Three seconds… it’ll be here in three seconds.”

Right after Vania finished speaking, outside the ship, just as Amuyaba was preparing a follow-up spore bombardment, its body suddenly froze. Its control over its own spirituality spiraled into chaos. Several spore bombs it was about to release exploded prematurely in its mouth. The monstrous form let out a painful shriek.

“What’s going on?! My... spirituality!”

Amuyaba’s twisted, piercing cry echoed through the night sky. Meanwhile, far away atop a sand dune, a cloaked Dorothy stood watching. She looked at the chaotic scene in the sky, then at her open palm.

In her hand was a small petri dish. Inside it, she could feel countless microscopic organisms dying rapidly.

“Wither… Die… At the end of your evolution, let extinction be your final form... BS61-1… Your mission is over.”

Staring at the petri dish, Dorothy murmured softly. Inside wasn’t just any material—it was the virus strain responsible for the Withering Plague. In the microscopic world invisible to the naked eye, they were dying in droves. And not just these ones—every identical virus strain in the world.

Far away in Bastis, in the even more distant tribal lands of Busalet, and in the refugee camp of Addus at the edge of the known world, all those tormented by the Withering Plague suddenly experienced relief. Their agony began to fade. Because the virus within them was dying.

“Perfect synchronic evolution… brings perfect synchronized extinction... This is the end of BS61-1. I wonder… can you see all this, Jemalhai?”

Sensing the changes in distant Bastis, Dorothy let out a soft sigh of relief. Her experiment had succeeded. BS61-1 was undergoing collective extinction. And the credit belonged not only to her—but also to Vania, to Dorothy herself, and to the Savior’s Advent Sect’s Redeemer, Jemal...

Dorothy’s solution for the BS61-1 virus was founded upon Jemal’s research. Through a series of studies, she identified several critical traits of BS61-1.

First: BS61-1 possessed a high-speed, autonomous evolutionary capability.

Second: its evolutionary direction followed the order of adaptability → transmissibility → pathogenicity.

Third: BS61-1 exhibited periodic synchronized evolution.

With this understanding, Dorothy designed her experiment. She first introduced BS61-1 into the pseudo-history world. Within this alternate timeline, the introduced BS61-1 strain was isolated from its counterpart swarm in the real world. It became an entirely separate population whose evolution no longer synced with the BS61-1 of the real history.

Next, Vania injected herself with BS61-1, using her own body as a host to allow the virus to reproduce. Then, by using her powers to strengthen her immune system, she would destroy the virus. During this process, she “trained” the virus, forcing it to mutate and evolve more rapidly.

The virus’s evolutionary pattern followed an adaptability-first principle—in other words, adaptability was always the top evolutionary priority. The virus would evolve its anti-microbial resistance first to survive against Vania’s enhanced immune assaults.

Vania repeatedly allowed the virus to breed within her, then purged it with her immune power. After each purge, she reinfected herself and repeated the process, continuously placing the BS61-1 strain in the pseudo-history under extreme survival pressure—forcing it to prioritize adaptability over and over again.

Eventually, even when Vania—with ritual enhancements—could no longer purge the virus through healing alone, she began injecting herself with other pathogens, giving BS61-1 even more competition for survival.

Dorothy’s goal was to continuously compress BS61-1’s evolutionary choices—to push it to evolve adaptability, immunity resistance, and anti-microbial traits above all else. If this virus were a “player” in a game, Dorothy, as the game’s designer, was forcing it to allocate every single skill point into adaptability.

But biological evolution is not without limits. Viral evolution has a ceiling. BS61-1 was still a physically limited organism—it couldn’t evolve all its bodily structures solely for adaptability. Just as a person holding swords in both hands would need to use their mouth or feet to wield a third, but doing so would mean sacrificing walking ability.

Under relentless survival pressure from Dorothy, BS61-1 pushed all its redundant structures to the extreme—turning everything it could into “weapons” against other microbes. Yet when that still wasn’t enough, it began cannibalizing other vital biological functions.

It was like a player reallocating all their skill points to Strength—completely stripping away points from Agility, Intelligence, and Endurance just to eke out more power.

To evolve greater adaptability, BS61-1 began “refunding” its other attributes.

First, it devolved its pathogenicity, meaning infections caused no symptoms and it lost the ability to absorb spirituality.

Then, it devolved its transmissibility, making it nearly impossible to spread between humans.

Next, it devolved its reproductive ability, so it could no longer replicate within a human host.

And the most ruthless part… after nearly half a year of experimentation, Dorothy finally forced BS61-1 to devolve its self-sustaining ability. The virus could no longer absorb or process nutrients to stay alive.

Only by Vania actively using her powers to "heal" the virus—offering her own Chalice as a life support—could the virus survive. What was once a parasitic, spiritually-draining pathogen had become one that needed external spiritual “handouts” just to keep living.

The moment such a virus strain—one that couldn’t even sustain its own life—was produced and divided, it was like a severely deformed infant born without lungs. It should have died instantly, long before the synchronized evolution phase could occur.

But Vania healed them.

She extended their lives through artificial means, allowing these mutated strains with absurd adaptability to survive long enough to reach synchronization time. At that moment, all BS61-1 strains in the pseudo-history synced to this newest, most deformed form.

Dorothy and Vania conducted this experiment repeatedly—selecting for ever more dysfunctional, dependent variants.

By this stage, the BS61-1 in the pseudo-history had become a virus that could only survive with external aid—one that could only persist in a lab environment. The moment it left such conditions, it would perish. But in terms of adaptability—its microbial resistance—this malformed BS61-1 was unmatched. Evolutionarily, it was everything BS61-1 had ever prioritized.

BS61-1 underwent synchronized evolution every hour. So when Dorothy and Vania returned to the real history with the virtual strain timed precisely, the BS61-1 populations in both timelines reconnected. At the moment of synchronization, this “advanced”, high-adaptability, deformed version was shared to all BS61-1 viruses in the real world.

Suddenly, all BS61-1 viruses became malformed strains—unable to live without external spiritual supplementation or lab environments.

Naturally, ordinary human patients could not “feed” spirituality to their viruses. Nor were their bodies lab conditions. Thus, the moment synchronization completed, the virus began mass-dying.

Within mere seconds, the BS61-1 virus vanished from the world. The plague ended in an instant.

Amuyaba hadn’t even realized what had happened—its massive spiritual supply was abruptly cut off, and its spirituality spiraled out of control.

Across Busalet, countless people tormented by the Withering Plague suddenly felt their pain vanish. Those who had collapsed in agony slowly and unbelievably stood back up. In villages, on streets, within tents—they looked around, weak but stunned. One by one, smiles bloomed on their faces.

“It’s gone… it doesn’t hurt anymore! What’s going on?”

“I’m healed? I’m really healed?! Incredible—what just happened? My Lord… was it You who saved us?”

“Ancestors… thank you for your blessings.”

“God! Thank You for Your mercy!”

At that moment, across all of Busalet, millions rejoiced. They cheered. They gave thanks. Their words differed—but all their gratitude seemed to echo in Vania’s heart.

“Everyone… is healed? That’s wonderful… It was all worth it…”

Inside the chapel aboard Ivy’s vessel, Vania held her chest with closed eyes, whispering softly to the voices swelling in her heart.

And outside the ship, in the night sky—a new, shrill scream tore the air.

“What did you do?! You steel bitch!”

Furious, Amuyaba charged straight at Ivy. Seeing this, Ivy turned to Vania and spoke.

“Sister Vania, please head to a secure chamber. I’m about to engage that creature in close combat—this place is not safe.”

Hearing Ivy’s words, Vania opened her eyes and looked toward the distance. Her pupils shimmered faintly with gold, as if she could see through steel walls to the rapidly approaching Amuyaba.

“Sister Ivy… now is not the time for me to flee. Please allow me to stand with you—to eliminate the source of this land’s suffering.

“In the name of the Merciful Holy Envoy…”

As she spoke, a wave of sacred, gentle radiance erupted from her body, illuminating the entire chapel.

After saving millions of plague victims across Busalet, Vania had at last completed her mission of relief—and completed her advancement ritual.