The Three-Dimensional Maneuver Gear
"Serian Elhardt."
In the deepest part of the imperial palace, the audience chamber of the Sun Palace. The Emperor’s gaze, from where he sat upon the throne, turned toward the girl standing below the dais. Serian took one step forward and knelt with flawless posture. The silver hair that caught the chandelier light swayed gently.
"Cardinal Academy’s top graduate. I hereby appoint you as the Empire’s Special Imperial Armaments Development Officer."
At the Emperor’s gesture, an attendant approached and presented an appointment letter adorned with magnificent gold thread. Serian accepted it with both hands in a show of perfect courtesy and bowed deeply.
"I will devote my loyalty to the glory of the Empire, Your Majesty."
Her attitude was flawless, her expression reverent. No one noticed the faint tremble at the corner of her mouth.
A murmur spread among the ministers and nobles below the dais. It was a mixture of admiration, jealousy, and astonishment.
"An Armaments Development Officer at that age? There’s no precedent."
"It’s possible for the Elhardt family. One of the Empire’s five great magical houses, after all."
"If she’s the Emperor’s personally appointed development officer, becoming chief of the Armaments Bureau is only a matter of time. After that, maybe even vice minister of military affairs…?"
"A truly smooth path. I’m green with envy."
Their eyes glittered with longing and envy. Imperial Special Armaments Development Officer. The core of the Armaments Bureau. The position that oversaw all military technology development. A guaranteed lifetime of power and wealth—the very peak of success in anyone’s eyes.
But the person who had actually received the position—Serian, or rather, me—was screaming inside.
We're fucked…
Because I knew. This seemingly brilliant Empire, Grandia, would be completely destroyed in just a few years. It would collapse utterly in the war against the Holy Astra Empire, leaving nothing behind. The memories of my past life, which had resurfaced like a nightmare a few days ago, had told me so.
This world was the setting of the game my past-life favorite game streamer had played on his broadcasts. Lost Empire. I didn’t remember the story in detail, but one thing was crystal clear.
This empire was a disposable background nation meant to highlight the greatness of the protagonist’s country by falling spectacularly.
What rotten luck.
Just a few weeks ago, my life had been perfectly smooth sailing. Born as the only daughter of the Elhardt ducal house—one of the Empire’s most prestigious magical families—I had graduated at the top of every subject from Cardinal Academy, the greatest educational institution in the Empire. My major was armaments manufacturing and alchemy, but I had also taken first place in magical theory, practical application, and applied magic studies with overwhelming scores.
I had just turned twenty, yet I was already a recognized 4-star mage by the imperial family. Right after graduation, scouting offers from every department had bombarded me like carpet bombing.
…And yet, of all times, right when everything was perfect, my past-life memories had returned without warning. The memories of an ordinary engineering student from South Korea. And the most important piece of information those memories brought was that this country was doomed.
Fucked. Fucked. So fucked…
Completely, properly fucked.
Inside the carriage leaving the imperial palace and heading toward the Armaments Bureau, Serian repeated the words desperately in her mind. This country would soon be shattered. It would fall to the enemy invasion and vanish from the map. That future was already set in stone.
And the people holding high office in the Empire would naturally be held responsible for the defeat. Their heads would be chopped clean off or they would rot in enemy prisons for the rest of their lives.
She had to run. She had to escape this Empire no matter what. That single thought filled her head.
But the method was the problem. She couldn’t just resign and walk out. The war had lasted decades. Even if it was only nominal, they were currently in a state of war. A high-ranking official deserting at a time like this? That wasn’t resignation—it was clear treason.
The moment she received the appointment letter directly from the Emperor, her freedom to leave as she pleased had vanished.
…Right. I need to get fired.
Whether by causing an accident or completely ruining a project, she had to be kicked out by someone else’s hand rather than leave on her own. That was the only escape route.
But—another problem arose here.
The person known as “Serian Elhardt” was simply too perfect a talent. The greatest genius in Cardinal Academy’s history. The youngest 4-star mage. An all-rounder who excelled in both theory and practice. On top of that, the sole heir of the Elhardt family, one of the five great magical houses.
If someone like that suddenly started acting like an idiot the moment she took office, she wouldn’t be called a parachute hire or a lightweight—she might be suspected of being a spy. In that case, execution would be certain.
If only I’d been born a commoner. I could’ve just fled to the countryside.
Damn it. Who knew her life being too smooth would come back to bite her?
For now… let’s make a plan.
Serian’s mind spun quickly.
I’ll make things that look plausible on the surface but are completely useless in practice, and churn out failure after failure.
Armaments development? Fine. She would use every scrap of her past-life knowledge to mass-produce flashy pieces of garbage. She would waste the defense budget like water and bleed it dry with glee. Then, before long—
She would be labeled something like “a hothouse flower who only knows theory” or “an incompetent noble girl who doesn’t understand the world” and pushed into a powerless position.
And at the right moment, she would shed a single tear and say,
“This heavy responsibility seems beyond my capacity.”
If she submitted her resignation then, everyone would nod in agreement. “She was such a diligent child, though,” they would say.
It was a perfect plan. At least, that was what Serian thought.
At the main entrance of the Armaments Bureau, the person who greeted Serian was a neatly dressed man.
“You must be Lady Serian Elhardt. I’m Martin, administrative officer of the Armaments Bureau.”
“I’ll be in your care.”
Serian gave a short bow and followed behind him. The interior of the building was far larger than she had expected and incredibly busy. Research labs, testing rooms, and workshops lined both sides of the corridor. The sound of hammers never ceased. The air carried the smell of iron and the lingering scent of mana.
It smelled nothing like the magic academy.
“The Armaments Bureau is divided into the Research and Development Department, the Testing Department, and the Manufacturing Department. When a development officer like yourself submits a proposal, the departments cooperate to produce the actual item.”
As Martin continued his explanation—
“You’re here.”
A heavy voice rang out from the far end of the corridor. Martin reflexively straightened his back.
“Chief Development Officer, sir!”
Silver hair, a well-groomed beard, and a perfectly pressed uniform. The man in his mid-fifties carried a military air in his very stride. Chief Development Officer Valentine. The real power within the Armaments Bureau. He was a living witness to the Empire’s weapons technology.
A new development officer… how many years has it been?
His gaze swept over Serian. Then he clicked his tongue inwardly.
She was far too young. Her skin was flawless, and her hands showed not a single callus. She looked freshly twenty. A face that had probably never stood before a forge, let alone seen war.
And they’re putting her in the development officer seat?
It was absurd. The position of development officer was never a light one. The reason the Empire had endured this long was because this very bureau had wrung out blood and sweat day and night to produce weapons.
Veteran craftsmen who had hammered iron for decades. Practical veterans who had survived among the top graduates of the armaments academy. That was the standard for this position.
Yet—
A magic academy graduate? Majoring in armaments manufacturing?
Valentine snorted inwardly. That was merely a hybrid academic discipline that only knew how to talk about manufacturing without any real-world experience.
Clearly pushed in through connections.
Serian’s surname—Elhardt. One of the five great magical houses. At a glance, she was unmistakably a parachute hire.
Valentine reluctantly extended his hand.
“I am Chief Development Officer Valentine.”
“I am Serian Elhardt. I look forward to working with you.”
Serian bowed with impeccable grace. Her silver hair swayed neatly. A cool impression. A posture without a single gap. Refined speech. She looked every bit the proud noble daughter with a strong sense of self-worth.
Just as expected from one of the five great families, an aloof arrogance was etched into her features.
These types only cause friction once they enter an organization.
Valentine let out a quiet sigh. There wasn’t a single thing about her that he liked.
I’ll have to break her spirit thoroughly from the start.
He immediately sharpened the edge of his words.
“I hear you’re from the magic academy? How much practical manufacturing experience do you have?”
Serian answered without hesitation.
“I believe I still have much to learn.”
As expected. Valentine sneered inwardly. She was pretending to be humble, but in the end she was admitting she was an inexperienced rookie with no real skill.
“Then you’ll start with simple tasks.”
He deliberately spoke each word with emphasis so that everyone could hear.
“Reinforcing the durability of existing weapons or improving armor defense. It’s best to start from the basics again.”
Know your place and don’t even dream of innovation. The blatant message was clear.
He had been seething at the ridiculous rumors floating around inside and outside the bureau—youngest development officer, next vice minister candidate, and so on.
Let’s see how long this arrogant young lady can last.
However—
“That sounds good.”
Serian answered without the slightest disturbance. Her expression and tone were completely calm. She even looked… relaxed.
Well, from Serian’s perspective, it didn’t matter.
Rather, it’s perfect. Failing at simple tasks will cause even greater disappointment.
Things were proceeding according to plan.
But from Valentine’s perspective, her attitude was interpreted in a completely different way.
Most mages had enormous pride. Especially one from the five great families—she should have been flustered by such blatant disregard, or at the very least shown some displeasure.
Yet—
…What is that smile?
Valentine had definitely seen it. For the briefest instant, the corner of her mouth had curved up ever so slightly. It wasn’t an expression born of confusion.
It was—
You’ve spent decades doing nothing but work like this?
—the arrogant leisure of someone who seemed to be saying exactly that.
The Armaments Bureau. The headquarters of the Empire’s weapons technology. The soul of craftsmen who had poured their entire lives into fire and iron for decades. And this fresh graduate was looking down on all of it.
For a moment, it felt like his heart dropped. Blood rushed to his head.
This… arrogant brat…!
In Valentine’s office, a woman in work clothes stood across from him. Her hair was neatly tied back, her posture efficient. Senior Development Officer Ella—Serian’s direct superior.
“Chief. What project do you plan to assign the newcomer?”
At Ella’s question, Valentine immediately tossed a single document onto the desk as if he had been waiting for it.
“This. A siege weapon for the Silver Horn Fortress recapture operation.”
Ella’s face hardened instantly.
“Chief. You clearly said you would start her with basic performance adjustment duties.”
“Did I?”
Valentine asked back leisurely. A twisted smile hung at the corner of his mouth.
“The youngest has only just arrived, hasn’t she? Giving her that on her first day seems a bit—”
“Youngest?”
He snorted.
“It would be rude to treat the greatest genius in Cardinal Academy’s history as a mere rookie.”
Ella was at a loss for words. Why is this man acting like this again? She had planned to let the newcomer start comfortably, but she couldn’t tell if he was serious or joking.
“Chief, that fortress…”
Ella spoke carefully.
“…is a place where recovery attempts have failed for over ten years because of the mana barrier.”
The Silver Horn Fortress. A strategic stronghold occupied by the enemy empire’s archmages. The mana barrier surrounding its walls neutralized all attacks.
“It’s impossible to even strike the wall itself…”
Ella swallowed a sigh.
Just what did the newcomer do to get her first assignment like this?
Whatever it was, she had clearly been marked.
Valentine crossed his arms and spoke mockingly.
“She’s a genius, isn’t she? Let’s trust her. They say she’s the best in Cardinal Academy’s history, so she’ll surely come up with something ingenious.”
Of course, he didn’t have even the slightest expectation. She would probably just scribble down the obvious—make the existing catapult bigger, increase the mana shell payload. That would be the perfect moment. He would thoroughly humiliate her.
“Where should I work?”
“This way, please.”
The place Martin guided her to was a private laboratory at the very end of the third floor. It was much larger than expected and had excellent lighting. Alchemy equipment, experimental tools, recording stones, and measuring instruments were all neatly organized.
“If you need any materials or equipment, please let me know anytime. The budget is… quite generous.”
Martin smiled as he handed over a thick stack of documents.
“These are the blueprints and performance data for existing armaments. I brought them for reference.”
“Thank you.”
Serian answered half-heartedly and flipped through the pages. It was exactly as she expected. Swords, spears, shields, armor, catapults, ballistae… typical medieval fantasy weapons. All things she had seen before.
Well, what I know is far better than any of these.
Countless weapons from the creative works she had enjoyed in her past life flashed through her mind. The vertical maneuvering equipment of the charging giants, superhero suits, boarding-type combat weapons, railguns, plasma cannons…
Of course, perfectly recreating them with this world’s technological level was impossible. But—if she mixed in magic and alchemy appropriately and only borrowed the principles?
She might be able to produce something that looked convincing.
Right, then. Let’s begin the first budget-wasting project.
Her eyes stopped on one item within the stack of documents.
「Silver Horn Fortress Recapture Operation」
Can’t destroy the wall?
Serian let out a small laugh.
Then just go over it.
Something easy to make, that looked innovative on the surface, yet required such extreme skill that its actual combat practicality was near zero. And something that would devour an enormous amount of production costs. There was a perfect candidate.
Serian sat at the desk, spread out a sheet of parchment, picked up her pen, and wrote the title.
Project Name: Three-Dimensional Maneuver Gear
Since it was a project that would fail anyway, she had decided to just kill time with it. But the moment she began sketching—
The blood of the engineering student from her past life began to boil.
Compressed mana injected from gas cylinders worn at the waist would launch wire anchors. The recoil would pull the body forward. Auxiliary propulsion devices using magic inscriptions would handle direction changes and acceleration. A hilt-shaped control device would operate both anchor launch and injection—
Her past-life knowledge connected with this world’s magical engineering and alchemy theories, creating powerful synergy. It was redesigned within the limits of this world’s technology, and a new conceptual structure that transcended existing principles through magic took shape.
Huh… this is more fun than I thought?
Once she picked up the pen, she couldn’t stop. She didn’t even notice time passing.
And so—several days flew by in the blink of an eye.
A few days later, Serian’s proposal was placed before Valentine and the senior development officers.
Valentine snorted as he picked up the document.
I wonder what absurd nonsense she wrote…
He already had mocking words ready on the tip of his tongue.
“Three-Dimensional Maneuver Gear…?”
The title alone sounded like complete nonsense. But the moment he turned the first page—
Valentine’s expression changed. Then the next page, and the one after that. His eyes gradually widened. His mouth fell half open. The senior development officers beside him reacted the same way. The only sound in the office was the rustling of pages being turned.
And then—the silence was broken by a trembling voice.
“Is… is this… really possible?”
Everyone had been pondering the same question: How do we destroy the wall?
But Serian’s proposal seemed to answer like this:
Why destroy the wall? Just fly over it.
Of course, there had been methods to “go over” the wall before. Throwing grapples or using siege towers had been employed for hundreds of years. But they were powerless before the rain of arrows and magic pouring down from atop the barrier.
Mages capable of flight magic were extremely rare across the entire Empire, and the troops they could transport were far too few.
But this proposal was different.
Valentine swallowed dryly. According to this design—even ordinary soldiers who could not use magic could climb the walls and perform acrobatic maneuvers in the air to evade enemy attacks simply by wearing the device.
It wasn’t climbing. It was flight. Soldiers flying across the wall as their stage. The very landscape of war would change in an instant.
“Because of the mana barrier, we can’t even approach… How…?”
Someone muttered. Valentine quietly pointed to the blueprint.
“Here.”
Where his finger landed—
“The anchor tip is made of mana-penetration alloy. It uses the gaps in the mana waves in reverse to generate instantaneous gripping force.”
Silence. It was a technology that had only existed in theory. And here was a method to realize it. From materials to manufacturing processes, even the magic circuits for each component—the proposal was at the level of a finished product.
In that moment, everyone instinctively realized.
This… will work.
If this equipment were completed, the legend of the impregnable Silver Horn Fortress would effectively be over. This was something that could shake the very paradigm of war.
Valentine could not tear his eyes from the document. What flashed before him was a silver-haired girl. Small, slender, with a youthful face. He had thought of her as nothing more than a hothouse flower, a talent who had entered through connections.
Was I wrong…?
A problem no one had solved for decades—she had solved it from an entirely different perspective in just a few days.
His lips moved on their own.
“…She’s a monster.”
And in that moment, every development officer in the Armaments Bureau learned the truth.
That the youngest, greatest genius in the history of the Imperial Armaments Bureau had been born. And that they themselves had become witnesses to that historic moment.
Of course, they had no idea that the genius in question was currently sitting in her laboratory, worrying over one thing:
How can I inflate the budget for this expensive, useless toy even more?