Chapter 44 – Crying Sound

Harpies, a swarm of Aerial Monsters that dyed the sky pitch black.

“Keeeee-!”

But this wouldn’t be all.

Unlike the past, when they came in small trickles and were defeated one by one, Monsters of this level instinctively knew which combat method was most efficient.

In other words, it was certain that Ground Monsters would follow behind them shortly. Of course, there was nothing to worry about.

“Ms. Sua. Please sound the air raid alarm.”

“Yes!”

Wiiiiiiing— Wiiiiiiiing—

The loud, ear-splitting sound of the air raid siren echoed.

It was a tool for the growing population of the Fortified City.

While it was, of course, to notify them that an attack was coming and they should evacuate… this was the Apocalypse. It was an era where those who could fight had to fight.

And… the proportion of those capable of fighting in my castle was exceptionally high. This was thanks to the systematic combat training that had been carried out.

“Now, fire!”

Ta-tat- ta-ta-ta-tat—

The citizens of the fortified city launched projectiles into the air using their respective abilities. Some used psychokinesis. Some manipulated stones, while others fired barely visible blades of wind.

Meanwhile, though not possessing firepower on the level of Sua or Seongjae, those who used water or fire could be seen here and there.

I marveled inwardly.

‘Oh. The number of good Ability Users has increased quite a bit…?’

Water and fire were useful, high-quality abilities anywhere.

This was especially true for the electricity abilities seen occasionally. Because in most places—where someone like Seongjae was rare—Electricity Users were still the primary means of producing electricity.

As Seongjae said, it would be very inefficient in the long run, but what could they do if that was all they knew?

This also meant that if they were living in another group instead of my castle, they might have secured a proper high-ranking position in that group.

However, they seemed satisfied with their current lives, fighting diligently without a word of complaint.

This was because living as “Citizen A” in my castle allowed for a far more luxurious life than being an executive in another group.

It was a positive phenomenon.

If they grew and became able to help, Sua and Seongjae wouldn’t have to be so immersed in infrastructure maintenance tasks, such as filling the Water Tank or running the steam turbines.

Considering Sua, who had been showing considerable combat ability lately, or Seongjae, who had an enormous amount of work even if he just served as a boiler, this was truly a good development.

However, even if all those people participated in the battle… they could not overcome the sheer volume of the Monster swarm dyeing the sky black.

“Hold the line! We’re going to be pushed back at this rate!”

“We’re all going to die like this—!”

The moment they began to grow afraid.

Screech— Screeeech—

Just then, the fourth Interceptor was summoned.

“Hmm… I wanted to fill it up to about eight.”

Interceptors were most efficient when a certain number were gathered to sortie simultaneously and project firepower.

They weren’t Monsters; since they were machines, I couldn’t just send them out one by one as they were produced and risk losing Interceptors, which were incredibly expensive in material costs.

However, the situation didn’t allow for it. If I stubbornly tried to reach eight, unnecessary casualties might occur.

“Well… four should be enough. Sortie.”

So, I shrugged and gave the order. At my command, the four Interceptors immediately began ascending to the rooftop via the stairs.

* * *

Clank— Clank, clank—

Although they looked like small flying squirrels, since they weren’t Medium-Class, their size was essentially no different from a large dog.

Moreover, they moved around shaking thick tails that were almost as long as their own bodies, making them look almost awkward. Nevertheless, they headed toward the target point with agility.

Furthermore, since most of the body material was lightweight Mithril, their movement speed on the ground was quite fast.

It might seem insignificant, but this was a considerable advantage.

Even though they were aerial machines, they had four legs, meaning they weren’t machines that operated exclusively in the air.

That didn’t mean they fought on the ground, but like humanity’s airplanes, they had to come down and take time for reorganization after taking off.

This was… if one could call it a ‘limit,’ due to an innate ‘limit’ they possessed.

And that was…

The overwhelming, vicious performance that was unbecoming of a Medium-Class.

Whoosh— Flap—! Boom!

As they spread their wings, the thick tails unfolded, revealing their true identity. This was none other than a [Thrust Vectoring] jet engine.

Thrust vectoring nozzles, which are operated with some limitations even in the strongest modern fighter jets, are devices that change the direction of the jet engine’s exhaust.

Compared to that, the Interceptor’s tail engine…

Was a truly marvelous piece of equipment compared to modern fighter jets, capable of moving freely 360 degrees and adjusting the jet spray direction with ease.

Dive-bombing, sudden stops, sharp turns—they possessed every capability needed in the air, not only dominating evasion and tracking maneuvers but also possessing non-combat functions such as vertical takeoff and landing (VTOL) and hovering. But that wasn’t all.

The Interceptor was a machine with an incredibly complex structure, but in terms of functional aspects, it was actually simple.

Wings attached to four legs that could move freely.

A thrust-vectoring tail jet engine to add mobility.

But in truth, all of this was nothing more and nothing less than a means to deploy the…

No, to be precise, the [body itself], which was a Photon Autocannon. Come to think of it, the Interceptor was simply a [Photon Autocannon with wings].

And the performance of this Photon Autocannon was immense.

Not only did it have an overwhelming rate of fire, but it also possessed firepower that could not be called insufficient for aerial combat.

If it were on the ground, it would be unusable due to overheating issues. This was because Mithril was not a material with heat resistance as excellent as Adamantite.

However, in the air, there was no problem.

The Interceptor had numerous air intake ducts, which solved the overheating problem by cooling it with the overwhelming speed of the air.

The reason this insane performance was a disadvantage was as follows.

In terms of performance alone, it was no less than a Large-Class. If limited to its strength in aerial combat, the Interceptor feared nothing, not even a Super-Large Class…

But it was because this thing was merely Medium-Class.

As a Medium-Class machine, it could not handle the terrible amount of Mana consumption required to produce such vicious performance.

They could barely stay aloft for 10 minutes at most. Considering the time to fly to the battlefield and return, the actual combat time was only 3 to 5 minutes at most.

After fighting like that, they would return home like humanity’s aircraft, undergo a short reorganization, and sortie again.

This was also the reason why a Super-Large Class machine…

An [Aerial Mothership] was necessary to utilize them properly.

Of course, as it was now, they could be used without much trouble at the Main Base, where the Mana Facility and Production Facility were located.

K-boom—

And so, they began their first launch.

Four streaks of light emitted powerful force from the rooftop of the shopping mall, advancing toward the cloud of Monsters.

K-boom— Paaaaang!

A sonic boom erupted almost instantly.

Being lightweight, they broke the sound barrier in an instant.

‘Indeed, expensive materials are worth the price.’

I wore a satisfied smile.

It was a moment where I felt the reward for the hardship of finding Mithril.

Having reached the Harpy swarm in the blink of an eye, they—

Chiiiiiiing—

Let out a scream of insane high pitch.

It was as if, when the Gatling gun of a modern A-10 Thunderbolt attack aircraft fires, it isn’t an individual shooting sound…

But rather, a crushed vibration like a ‘vroom—’ echoing out. The firing sound of the Photon Autocannon was crushed, sounding like a high-pitched scream.

Did they fire for only about 0.4 seconds?

The scream did not last long.

However, the numerous streaks of light fired in a straight line.

Pierced right through the center of the Harpies…

Pa-pa-pa-pak!

And turned the cloud of the Harpy swarm into a donut shape.

It happened in an instant.

“Wha- what is this!”

“Th- that light… what on earth…”

“Could it be a new machine!”

“No… no way…”

Naturally, the Ability Users who were fighting with all their might from the ground city walls and inside the Defensive Facilities looked up at the sky with bewildered expressions. Of course, that bewilderment quickly turned into cheers of joy.

“Now’s the chance! Keep fighting!”

“Waaaaah!”

Not wanting to lose the momentum, the citizens of the fortified city began to fight as if pushing forward.

‘That’s how it should be.’

I grinned.

Meanwhile, the Interceptors passed through the Harpy swarm.

Chiiiiiiing—

They made a sharp turn and fired the Photon Autocannons once more. This was at a point where the Harpies that began to fall during the first shot had not yet hit the ground.

“Keeeee-!”

By the time the Interceptors successfully completed their first sortie and returned to the Main Base to be serviced by Worker Bugs, the number of Harpies had decreased by as much as half from the beginning.

But… there was no way I would be satisfied with just one sortie.

“If maintenance is done, sortie again.”

Whoosh— Flap—! Tu-ka-boom!

Once again, they carried out their second sortie.

* * *

Afterward, once the Aerial Monsters were cleared.

The Ground Monsters were also eliminated in an instant.

This was thanks to the firepower of the Adamantite Assault Cannons, which boasted powerful firepower after the explosive power enhancement research was completed, and the Interceptors, who began to eye the ground once there was nothing left to eat in the air.

The Interceptor’s weapon was specialized for the air, and although it lacked sustainability compared to the Assault Cannons, it was sufficiently effective against small and medium-sized Monsters.

And all these Mana Stones were mine.

Because as a contractual matter, I had stipulated that I would take all the Mana Stones from the city defense battle.

In the first place, I had built the Defensive Facilities, and I had killed most of them, so while they were grateful for saving their and their families’ lives, no one held a grudge.

Anyway, there were countless ways for them to obtain Mana Stones, such as through Dungeons. In particular, as agricultural reclamation began in the first Dungeon under Deokchan’s lead, the civilian income of Mana Stones increased enormously.

Meanwhile, Deokchan cautiously brought up the topic of borrowing a Rough Terrain Pioneer for agricultural land reclamation…

But I couldn’t do that yet.

Because there was still much to mine in the Desert Dungeon.

Setting aside the oil that happened to be found… the original reason for opening the Desert Dungeon was Mithril, but besides that, other ores like iron ore and Adamantite were also abundant.

‘Since I’ve already sent them, I might as well mine more materials.’

Furthermore, since I had produced a Large-Class Rough Terrain Pioneer and four Interceptors that consumed a truckload of Mana every time they sortie…

It was reaching a point where a single Mana Facility could no longer handle it.

If I set up one more Mana Facility, I could fill the currently lacking Mana Quantity and even produce one more Rough Terrain Pioneer for Deokchan (more accurately, for agricultural land reclamation).

Furthermore, I could increase Production Facilities or expand the military force.

“I can’t let this go. I really need to set up one more Mana Facility.”

With Mana Stones piling up, it was the perfect timing.