Aurora Deployment

 

「I said I’d handle it, but… is there even a weapon powerful enough to pierce a battleship’s armor…?」

Flack had gotten carried away in front of Kou, but now he was regaining his composure.

「Hm? Why do you think that?」

Arthur questioned the boy’s doubts.

「Big Mythology Weapons are based on warships, right? If there were weapons capable of piercing the armor of a warship in a single strike, space battles wouldn’t have even existed during the Interplanetary War era.」

「You have a sharp mind, boy. But there is a way. If it’s Outis and me, we can do it.」

「Really?!」

「Of course. With my Marmiadoise, we can pierce straight through.」

「How does that even work? Even a weapon developed by Kou-niichan couldn’t manage that, right?」

「Do not worry, boy. This is a collaboration between the super AI named after the great god of smithing and the Development Engineer who saved Planet Asia. The ultimate light. Yes, in other words—Aurora!」

Arthur declared it with such certainty that Flack found himself believing it without hesitation.

「That sounds… amazing. I’ll believe you. Maximizing output. We don’t know the reactor’s location, but if we aim to pierce straight through from the front or directly from behind…」

「The location of the heart—the reactor—is unknown. In that case, the best strategy is to maximize damage by piercing the ship from the front or the rear. …Let’s go with that, boy.」

「Yeah!」

Beside him, Unit 5 was fighting to protect Flack. In the skies above, exceeding an altitude of 2,000 meters, only a select few units aside from Transformable Silhouettes could maintain combat capability in silhouette mode—one of them being the Lanius C-Type.

「Kou-niichan, I’m moving to the front. Cover me.」

「Got it. Directly ahead, right?」

Kou replied while cutting down a Marid. Normally, a Silhouette midflight would be nothing more than target practice for fighter aircraft, but on Planet Libya, only allied forces possessed fighters.

Just as Arthur deployed the barrel of the Marmiadoise, Asia noticed something.

「Wait a second, Kou! That thing can definitely destroy it, but—!」

「You’re really using the Marmiadoise?! Flack, your output—」

「I’m going full throttle!」

「Wait—!」

There was no time to stop him. Arthur dodged the attacks from the Marids and Kakodaimons with movements as if dancing through the air. His acceleration far outmatched Unit 5.

「Here we go!」

「Unleashing—Aurora Deployment!」

Arthur leaped into Seth’s line of sight, locking onto his target.

For a brief moment, Flack felt as if he had locked eyes with Seth. Yet, no fear arose within him.

「To slay the wicked false god!」

He pulled the trigger. The attack, though resembling a laser, was visible. A crimson flash streaked through the air.

In that instant, a small hole appeared in Seth’s otherwise impenetrable head.

「Huh?」

The invisible trajectory of the shot manifested as a dazzling aurora, wrapping around the battlefield.

The aurora expanded gradually, creating an almost dreamlike spectacle.

Shifting from violet to blue, and then to green, the light spread across the sky.

「Impossible…」

Seth groaned. At that moment, internal explosions erupted in succession.

Even without pain receptors, there was no withstanding an internal detonation.

「That attack…!」

Seth lost its balance, teetering on the verge of plummeting to the ground.

「This is bad!」

At that moment, Garuda rammed into him, sending the falling Seth hurtling away to a distant location.

「Ah!」

Flack cried out.

The barrel of Marmiadoise had exploded.

「I’m sorry… I broke it…」

「Defeating Seth and protecting the people took priority. It’s not a problem.」

Arthur was tumbling headfirst through the air.

「Isn’t this situation a problem, though?!」

「I pushed my ailing body to its limits. It was a gamble, but—」

Without missing a beat, Unit 5 caught Arthur.

「Arthur, you’re not getting repairs anytime soon.」

「You can’t be serious!」

Kou sighed in exasperation at Arthur’s grumbling.

「I can’t believe I’m hearing that kind of complaint from a Silhouette… Well, it’s physically impossible. Realm doesn’t have any spare parts left.」

「So that’s the issue!」

「Exactly. We’ll cooperate for Libya’s sake, but… we’re in a tough spot.」

Arthur’s current form had been rebuilt using every last bit of Polymetis technology and the remaining parts found in Realm. Naturally, Kou could only design what was within his knowledge. He had merely adjusted the specifications and applied the technology available at the moment.

「Kou, what do we do? Astraea found out right away.」

There was no way to conceal the use of the Marmiadoise. After witnessing its sheer power firsthand, even Asia shook her head.

It was simply too dangerous.

「…It can’t be helped. At least Flack made it out safe.」

Kou shrugged, letting out a light sigh.

◆ ◆ ◆ ◆ ◆

「Seth neutralized.」

Aki’s voice echoed hollowly.

As a Gunsmith, even she struggled to comprehend the nature of the attack. Above them, the aurora continued to ripple through the sky.

「It seems the enemy still has some operational capability left. We can’t let our guard down… nya.」

Nyanta was so dumbfounded that her usual ‘nya’ felt like it was added forcefully at the last moment. As a Wildcat, she had studied various optical weapons extensively. But this wasn’t a weapon that could be mounted on a Silhouette. Even for a warship’s main artillery, reproducing that level of power seemed highly questionable.

「I will confirm this matter with Kou later. Minimize unnecessary inquiries to him.」

Astraea’s words made the ship’s crew nod in agreement.

「Astraea, may I ask you a question?」

A secret transmission came from the Hiyou, sent by Kinukawa.

「Go ahead.」

「Is a weapon like that even possible? A visible laser… that explodes?」

「No, Kinukawa. That was not a laser cannon. It was an antimatter cannon—specifically, a positron cannon.」

「What?! Or rather… that makes sense.」

A superweapon of impossible scale for a Silhouette—a phenomenon beyond comprehension.

「Descending electrons were detected. Normally, this is a disturbance phenomenon seen in the polar ionosphere.」

「Descending electrons… also known as auroral electrons.」

Kinukawa had heard of the phenomenon before.

The polar ionosphere—where high-density plasma in the upper atmosphere over Earth’s poles generates auroras. Interestingly, auroras are rarely visible directly over the poles themselves. Instead, the plasma forms an auroral oval, an elliptical region encircling the poles where the effect manifests most strongly.

「That Silhouette was created in the early Pioneering era of the Nemesis System. The Twelve Olympian AI designed it—an Another Level Silhouette. During the Interplanetary War era, every faction sought it as a strategic weapon.」

「A Silhouette from another dimension, huh… Can you explain the principle behind that cannon?」

「What appeared to be a laser was actually the path of the positrons. The extreme heat caused a time-delayed whitening effect, making it visible—but by the time you see it, the emission is already over. Think of it like a water jet cutter, where a high-pressure liquid is used to slice through materials. Here, the positrons were injected in a similar way, initiating annihilation reactions as they penetrated the target. The energy released not only pierced the target but also annihilated the matter along its trajectory—resulting in the explosion you witnessed.」

「So, the visible ‘laser’ was just a heat trail, and that aurora-like phenomenon was plasma generated from the collision between antimatter and the atmosphere… Meaning, there’s no way to block antimatter attacks?」

「Attenuation is possible. However, the current Mythology Weapons have no means of countering it. It was already discovered in the 21st century that lightning naturally contains positrons, triggering small-scale annihilation reactions within the atmosphere.」

Kinukawa nodded in understanding at Astraea’s explanation.

「If we compare it to the Solar System, it’s like a solar flare reaching Earth. A phenomenon on an astronomical scale.」

「Exactly. The aurora itself is created when charged particles emitted from the Sun collide with the atmosphere. During these collisions, even antiprotons have been detected. The aurora is essentially the result of antimatter reacting with the atmosphere at a quantum level.」

「So the Aurora—that extreme light—was caused by antimatter interactions.」

「Yes. Even my original would have been unable to create a Silhouette like that. Another Level Silhouettes are something else entirely.」

「But you and Kou… No, there’s no need to say it aloud.」

「Your assumption is correct. While we might be able to make something similar, miniaturizing it to fit within a Silhouette unit is utterly impossible.」

「So now that the weapon is destroyed, it can’t be replicated. Actually—Astraea, it’s better if it remains impossible to fully reproduce. Make sure Kou understands that as well.」

「You truly are a terrifyingly perceptive human. I’ll make sure he knows. And please, continue looking after him.」

「Of course.」

There was someone who truly understood what Kou had accomplished. That was a rare fortune—even for Astraea.

「We’ll need to have a proper discussion between the three of us sometime.」

「Without a doubt. Kou himself still hasn’t fully realized it yet.」

Astraea made no effort to hide her concerns.