Reincarnated in DxD With the 100X System

Mittelt's wings flared, her golden eyes narrowing in frustration.

I smirked, rolling my shoulders, feeling the raw energy in my muscles.

"Alright, cosplay angel. Let's see what you got."

She lunged—fast.

No spear. No magic. Just raw physical strength.

I barely had time to react before—

BAM!

A fist like a damn cannonball slammed into my ribs.

Air rushed out of my lungs, my body lurching backward from the sheer force.

Holy shit. She hits hard.

I skidded across the pavement, barely keeping my balance. But…

It didn't hurt as much as I expected.

Mittelt didn't let up. She pressed forward, her attacks relentless—a rapid flurry of punches and kicks, each strike refined and lethal.

Instinct kicked in.

I blocked. Dodged. Countered.

A punch aimed for my gut—I deflected it.

A knee strike—I sidestepped just in time.

A roundhouse kick—I raised my arm to block—

WHAM!

Her leg slammed into my guard, the sheer impact nearly lifting me off the ground.

Damn. That one actually hurt.

I stumbled back, shaking my arm.

That should've broken bone.

But instead?

It just stung.

Mittelt's cocky smirk flickered. She noticed it too.

"Oh? What's this?" she sneered, circling me. "You're not as squishy as most humans. What are you, some kind of experiment?"

I clenched my fist, flexing my fingers.

No…

I was just built different.

This was my base strength.

No buffs. No enhancements. Just me.

I exhaled slowly, my stance relaxing.

"Alright, my turn."

I moved—faster than before.

Mittelt's smirk vanished as I closed the distance instantly.

I threw a punch—aimed right for her stomach.

She blocked—just barely—her forearm absorbing the impact.

Her wings twitched from the force.

She wasn't expecting that.

I didn't let up.

I twisted, sweeping my leg low—she jumped.

But I anticipated it.

The moment she landed—I was already there.

CRACK!

A sharp elbow strike to her ribs—she winced, twisting away.

I lunged forward, my fist cutting through the air—

Mittelt gritted her teeth, her wings flaring as she pushed herself backward, escaping just in time.

She hovered midair, her breathing uneven.

"What the hell?" she spat, glaring at me. "You're… you're actually keeping up?!"

I cracked my neck, flexing my fingers.

"Keeping up? I'm just getting started."

Her brows furrowed.

Mittelt clicked her tongue.

"Tch. Fine. No more playing around."

She dove.

Fast.

Faster than before.

Her fist aimed right for my face.

I moved to dodge—

Too slow.

BAM!

Her punch slammed into my jaw, snapping my head to the side.

For a second, my vision blurred.

A normal human? That punch would've snapped their neck.

Me?

I just spat blood onto the pavement.

Mittelt stared.

I grinned.

"Damn. That actually tickled."

Her expression twisted—annoyance, frustration, a hint of panic.

She beat her wings once, lifting higher.

"Alright, screw this—I'm done playing."

With a snap of her fingers, a light spear materialized, crackling with holy energy.

The air hummed with power.

I exhaled, shaking the tension from my shoulders.

"Alright."

No more holding back.

Magic time.

With a flick of my wrist—

A pulse of mana exploded outward.

Intricate magical formulas flickered into existence.

Numbers. Equations. Raw computational magic.

Mittelt's smirk returned.

"Oh? Finally using that Sacred Gear of yours?"

I tilted my head.

"Sacred Gear?"

I let out a short laugh.

"Nah, cosplay angel. This is just math."

Her brow furrowed.

I raised a single finger.

"And unfortunately for you—"

"I'm really, really good at math."

The playful warm-up was over.

I exhaled slowly, rolling my shoulders as I shifted my stance.

My smirk hadn't faded—but now, there was an edge to it.

Something sharp.

Something dangerous.

"Alright, cosplay angel. You asked for it."

Mittelt didn't hesitate—she lunged again, her light spear humming with deadly energy, aimed straight for my chest.

But this time—

I didn't dodge.

Instead, I raised a single hand, my fingers tracing invisible symbols in the air.

A pulse of pure mana surged outward—reality itself distorting for a split second.

The moment her spear made contact—

CRACK!

It shattered.

Not blocked.

Not deflected.

Shattered.

Mittelt's eyes widened in shock.

"What?!"

She flapped her wings, retreating mid-air, her gaze flickering between me and the glowing remnants of her spear dissolving into golden particles.

The air around me crackled, arcane symbols and numbers spinning rapidly like a holographic code rewriting the laws of reality.

This was the result of hours of breaking down DxD's magic system.

The loopholes—the raw equations—the cheat codes hidden in plain sight.

And now?

I was about to demonstrate just how broken magic could be—in the hands of someone who actually understood math.

I smiled, my fingers still glowing with residual energy.

"I apologize in advance—I'm new to magic, so this might hurt way more than I intend it to."

Mittelt flinched.

She heard the playful tone, but the overwhelming pressure in the air made it clear—

I wasn't joking.

Then—

Before she could react—

Magic circles materialized behind me.

Not one.

Not two.

Dozens.

Glowing ominously, layered equations refining their effects into high-speed destruction.

With a simple flick of my fingers—

BOOM.

A blast of energy surged forward, a spiraling beam of compressed magic that warped the air around it.

Mittelt's eyes widened in terror.

She barely managed to cross her arms in front of her chest before—

CRASH!

The impact sent her flying, her small form crashing into the pavement with a sharp cry of pain.

The sheer shockwave from the spell rippled through the park, cracks splintering along the ground.

The ground beneath me cracked, deep fissures splintering outward as an unseen force erupted from within.

My magic surged violently through my body, unshackled, raw, untamed—yet somehow perfect.

A pulse of mana rippled through me, twisting the air, distorting reality itself. It wasn't just power—it was a resonance, a shift in existence, as if some fundamental truth had been forcefully rewritten within me.

Then—

It happened.

A force unlike anything I had ever felt before crashed into me like a tidal wave, my body no longer just my own. My very cells thrummed with something beyond human understanding, the sheer weight of creation itself pressing against my being.

My veins burned—not with pain, but with something deeper, something primal. Power flowed through me, a current of limitless potential. It wasn't just energy.

It was authority.

And then—

Light.

A blinding radiance erupted from my arms, golden streams of energy spiraling outward like molten metal being hammered into shape by the gods themselves. The battlefield trembled beneath me, the sheer force of my awakening sending powerful shockwaves in all directions.

The wind roared. Loose debris was flung skyward like fragile leaves caught in a violent storm.

Mittelt staggered back, shielding her face as the brilliance nearly blinded her.

Her wings fluttered, her body tensing—instinct screaming at her to flee.

And then, as suddenly as it had come—

It solidified.

The light compressed, reshaping itself, molding to my form. The radiant glow faded into something more refined, more controlled.

I lowered my arms, my breath steady—yet the power didn't fade.

I wasn't the same anymore.

My arms were no longer bare.

Instead, they were encased in gauntlets of pure energy, divine inscriptions glowing and shifting across their surface like living scripture. Ethereal circuits wove intricate paths across my skin, flames of raw magic flickering between them.

The very air around me shimmered and bent, reality distorting under the sheer magnitude of creation energy now coursing through me.

And then—

Knowledge flooded my mind.

A flood of information, absolute clarity, every function, every detail of my power laid bare before me.

『Sacred Gear Identified: Aetherius』

The words etched themselves into my soul, a revelation unfolding with pristine clarity.

🔹 Weapon & Armor Creation – I could forge weapons and armor at will, molding them from pure mana, enhancing them beyond natural limits.

🔹 Instant Weapon Mastery – Any weapon I created, I could wield perfectly. Not just skillfully—instinctively, as if I had spent a lifetime training with them.

🔹 Intuitive Forging – I didn't just make weapons; I understood them—every strength, every flaw, every way to optimize them for battle.

This wasn't just about creating things.

This was absolute mastery.

Aetherius wasn't a simple tool.

It was a divine forge—and I was its master blacksmith.

I exhaled slowly, flexing my fingers. The gauntlets hummed in response, shifting slightly, almost alive, as if awaiting my command.

The sheer craftsmanship of my own creation stunned me.

Perfect weight. Perfect balance. Every curve, every inch of the gauntlets was tailor-made for my hands, yet I had crafted them instantly, without effort.

I clenched my fists.

The air cracked.

Golden sparks danced at my fingertips, like embers from a divine forge. The first flicker of a blade's outline began forming—its shape unstable, fluid, as if the weapon itself was waiting for me to define its final form.

Mittelt, still staggering from my magic barrage, froze.

Her golden eyes widened, her breath shallow.

Her previous bravado?

Gone.

"...What… the actual hell is that?!"

Her voice barely came out, laced with disbelief.

She wasn't mocking me anymore.

She was terrified.

This wasn't supposed to happen.

Sacred Gears weren't supposed to awaken this fast.

They weren't supposed to radiate this much power instantly.

Yet me?

I was already in control.

I lifted my glowing hands, watching as molten strands of divine metal and raw energy swirled between my fingers, effortlessly molding into a weapon before my very eyes.

I grinned.

"Oh, don't worry about it."

I took a single step forward.

My aura surged, golden flames rippling outward, the sheer force warping the air around me.

Mittelt flinched.

I raised my hands—golden light crackling along the surface of my gauntlets, arcing like miniature thunderstorms.

Then, I smirked.

"Now then, cosplay angel…"

The energy in my hands condensed, shifting, reshaping—a sword of pure radiance forming in my grasp.

I pointed it at her.

"Round Two?"