The smell of dark roast espresso was the only thing standing between me and committing a violent war crime.
I pushed the heavy plunger down on my stainless-steel French press.
The rich, intoxicating aroma instantly filled the dusty, cavernous air of the castle kitchen.
It smelled like salvation.
It smelled like the total eradication of my morning fatigue.
Section Commander Hange Zoe was sitting directly across the massive oak table.
She was leaning forward, her elbows resting on the wood, her hands completely covered in grease.
She hadn’t blinked in exactly four minutes.
“Are you brewing some kind of alchemical stimulant?” Hange asked.
Her brown eyes were wide, magnified to comical proportions behind her thick, cracked goggles.
“I am brewing the will to live, Section Commander,” I deadpanned.
I poured the pitch-black liquid into a chipped ceramic mug.
“And as per our previously negotiated, legally binding verbal agreement, you will not speak to me until I have consumed exactly eight ounces.”
Hange literally bit her own lip.
She clamped her teeth down hard enough to draw a tiny drop of blood, desperately trying to keep herself from talking.
It was somewhat impressive.
Her lack of impulse control was a documented medical hazard, but her sheer dedication to scientific discovery was momentarily overriding it.
I took a slow, highly sophisticated sip of my coffee.
The caffeine hit my bloodstream like a localized lightning strike.
The lingering, suffocating exhaustion from scrubbing the castle cellars completely evaporated.
My unified mind booted up to maximum capacity.
The Peter Parker intellect instantly began running complex metallurgical algorithms in the background.
The Leon S.
Kennedy survival instincts maintained a constant, 360-degree threat-assessment sweep of the room.
I was fully operational.
And I needed resources.
Standard military blades were structurally useless against the Armored Titan.
Reiner Braun’s biological plating possessed a density roughly equivalent to depleted uranium.
Swinging a piece of forged steel at it was a kinetic joke.
I closed my eyes, taking another sip of the scalding black coffee.
I mentally opened my digital inventory.
I had exactly two Exchange Tickets remaining.
‘System,’ I commanded silently.
‘Execute multi-pull.
Prioritize offensive ballistics and cognitive sustainment.’
The digital slot machine materialized in the pitch-black void of my mind.
It spun with a quiet, melodic chime.
Two solid silver lights flashed in rapid succession.
‘[Congratulations!
Host has pulled [Rare] Tier Rewards!]’
‘[Item Acquired: Industrial Blueprint – Shaped Charge Explosive Casing.]’
‘[Item Acquired: Minor Focus Serum (Cognitive Enhancer).]’
I smirked into my ceramic mug.
The system was officially tired of me complaining about my lack of firepower.
A shaped charge wasn’t just a bomb.
It was a directional kinetic penetrator.
It was a masterpiece of modern explosive geometry.
By lining a hollow cavity of explosive material with a conical metal liner, the detonation wouldn’t just blast outward in a useless sphere.
It would take the entire explosive force, compress it, and invert the metal cone into a hyper-pressurized, superheated jet of molten plasma.
It would melt right through Reiner’s armor like a hot knife through butter.
I was going to build a Thunder Spear three years ahead of schedule.
And I was going to make it significantly more lethal.
The second item, the Minor Focus Serum, dropped directly into my digital inventory grid.
‘[Utility: Eliminates cognitive fatigue.
Increases mathematical processing speed by sixty percent for exactly four hours.]’
It was a small, glowing blue vial.
Perfect.
I was going to need every single drop of brainpower to machine titanium without modern industrial tools.
I set my coffee mug down on the oak table with a sharp clack.
“Alright, four-eyes,” I sighed, rolling up the sleeves of my military jacket.
“Show me the titanium.”
Hange squealed.
It was a high-pitched, piercing sound that severely disrupted my inner ear.
She practically vibrated out of her wooden chair.
She grabbed the heavy iron crowbar resting on the floor and slammed it into the massive wooden crate she had hauled in earlier.
With a loud screech of tearing nails, the lid popped off.
Inside the crate, packed in rough straw, were a dozen heavy, dull-grey metal ingots.
“I requisitioned these from the deepest vaults of the Interior Military Police!” Hange practically yelled, bouncing on her heels.
“It’s an experimental alloy!
They found the ore in the northern mountains ten years ago, but the blacksmiths couldn’t forge it!”
“They said it was too brittle!
Too stubborn!
They couldn’t make blades out of it!”
I reached into the crate and pulled out one of the ingots.
It was surprisingly light for its volume.
I ran my thumb over the rough, unpolished surface.
“They failed because they treated it like high-carbon steel,” I analyzed coldly.
“Titanium possesses a completely different atomic lattice structure.”
“If you heat it in a standard coal forge without an inert gas shield, it violently absorbs oxygen and nitrogen from the atmosphere.”
“It creates a severe, microscopic embrittlement layer on the surface.”
“They didn’t forge a weapon.
They baked a giant, metallic cracker.”
Hange stared at me, her jaw literally hanging open.
She pulled a small, incredibly messy notebook from her jacket pocket and began frantically scribbling everything I had just said.
“Oxygen embrittlement!” Hange muttered, her eyes wide with manic realization.
“Of course!
The atmospheric interference corrupted the lattice!”
“How do you know this?!” she demanded, pointing her charcoal pencil at my face.
“I read a lot of books when my brother is yelling,” I deadpanned, turning the ingot over in my hands.
“And I possess an inherent, almost supernatural lack of patience for structural inefficiency.”
“We are not going to make swords out of this, Section Commander.”
“Swords require a razor edge.
This alloy won’t hold a monomolecular edge without specialized heat treatments we mathematically cannot achieve in this castle.”
“So what are we going to do with it?!” Hange asked, practically climbing onto the table.
“We are going to make a gun,” I stated flatly.
“A very large, very explosive gun that straps directly to the forearm of our ODM gear.”
I walked over to the massive iron hearth on the far side of the kitchen.
I had spent the last two hours completely converting the cooking stove into a crude, highly pressurized blast furnace.
I had hooked my modified, high-pressure ODM gas nozzle directly into the air intake of the hearth.
By bleeding a slow, constant stream of pressurized oxygen into the coal fire, I had exponentially increased the combustion temperature.
The fire inside the hearth wasn’t orange.
It was a blinding, furious white.
The heavy wooden door to the kitchen suddenly creaked open.
A young Survey Corps scout walked in, carrying a massive canvas sack over his shoulder.
He looked entirely exhausted, his green cloak covered in a thick layer of grey soot.
“Delivery from the logistics depot, Section Commander,” the scout mumbled, dropping the heavy sack onto the flagstone floor.
“Black powder, high-tension steel wire, and the hollow iron casings you requested.”
“Appreciated,” I noted, walking over to the sack.
I mentally accessed my inventory while my back was turned to Hange.
I materialized a spare, foil-wrapped protein bar into the palm of my hand.
I casually tossed it to the exhausted scout.
He caught it awkwardly against his chest, looking down at the shiny modern wrapper in complete confusion.
“What’s your designation, cadet?” I asked, pulling a roll of high-tension wire from the sack.
“Scout 157, sir.
Callsign Black Dragon,” he replied, blinking at the peanut-butter chocolate bar.
“Well, Dragon,” I deadpanned, not looking up from my work.
“You are currently the only person in this decrepit castle who actually delivers useful items on time.”
“Consume that ration immediately.
It contains highly concentrated survival nutrients.”
“And don’t let Captain Levi catch you tracking soot onto his newly sanitized floor, or he will mathematically disassemble your skeleton.”
Scout 157 nodded rapidly, his eyes widening in terror at the mention of the Captain.
He shoved the shiny wrapper into his pocket and scrambled out of the kitchen, shutting the heavy oak door behind him.
I hauled the sack of black powder onto the table.
“Hange,” I ordered, slipping entirely into my tactical commander persona.
“I need you to measure out exactly four ounces of this black powder per casing.”
“Do not exceed four ounces.
If you pack the powder too tightly, the concussive yield will shatter the titanium housing before it can project the shaped plasma jet.”
“We want a directed explosion, not a hand grenade.”
“I’m on it!” Hange yelled, grabbing a brass measuring scale.
I turned my attention back to the titanium ingots.
I needed to melt them down and cast them into hollow, conical liners.
I didn’t have an inert gas shield.
But I had Peter Parker’s brain.
I grabbed a massive block of raw, scavenged flux and a handful of crushed charcoal from the bin.
“I can create a localized, sacrificial carbon-dioxide barrier to shield the molten metal from atmospheric oxygen,” I muttered to myself.
I threw the titanium ingots into the heavy graphite crucible.
I packed the crushed charcoal and flux thickly over the top of the metal.
Using a pair of heavy iron tongs, I shoved the crucible directly into the blinding white heart of the blast furnace.
“Now we wait,” I said, leaning back against the stone counter.
I pulled the small, glowing blue vial of the Minor Focus Serum from my pocket.
I popped the cork and downed the liquid in a single shot.
It tasted like blueberries and cold electricity.
A sudden, sharp wave of absolute, terrifying clarity washed over my brain.
The background noise of the castle completely faded away.
My mathematical processing speed violently accelerated.
I could literally see the geometric equations floating in the air.
I could calculate the precise melting point of the titanium alloy based purely on the radiant color of the crucible.
I could measure the exact tensile strength of the high-tension wire just by looking at the coil.
It was a beautiful, overwhelming sensation of pure genius.
‘[Cognitive enhancement active.
Parker Template operating at 160% capacity.]’
“Kai, look!” Hange shouted, entirely ruining my moment of zen.
She held up one of the hollow iron casings.
She had packed the black powder perfectly, capping the bottom with a wooden plug.
“Excellent,” I said, my voice vibrating with focused energy.
I grabbed the iron tongs and pulled the glowing, white-hot crucible from the furnace.
The flux and charcoal had burned away, creating a perfect, oxygen-free pocket.
Inside the crucible, the titanium had melted into a sloshing, blindingly bright pool of liquid metal.
I poured the molten titanium into the conical clay molds I had prepared earlier.
The metal hissed and spat, radiating a wave of blistering heat across the kitchen.
“Once these cool, we insert the cones into the top of the powder casings,” I explained rapidly, my hands moving with blurring speed.
“We attach a friction-based spark fuse to the base.”
“We rig a deployment track to the forearm of the ODM harness using the high-tension wire.”
I grabbed my red toolbox, pulling out a handful of brass screws and my heavy-duty Duck Tales tape.
“When you fire the anchor trigger, a secondary spring-loaded mechanism launches the entire iron casing forward.”
“The casing embeds itself directly into the Titan’s armor.”
“The friction wire pulls taut, igniting the fuse.”
“The black powder detonates.”
I grabbed a piece of chalk and drew a rapid, flawless diagram on the wooden table.
“The explosion hits the back of the titanium cone.
The cone inverts under the extreme pressure.”
“It fires a jet of molten metal directly through the armor plating, penetrating the nape, and annihilating the spinal connection.”
Hange was vibrating so violently I thought she was going to spontaneously combust.
“It’s a localized, armor-piercing kinetic missile!” she screamed, gripping her hair.
“It completely bypasses the limitations of standard blade friction!”
“Kai Yeager, you are a beautiful, terrifying genius!
I want to marry your brain!”
“I am twelve years old and emotionally unavailable, Section Commander,” I deadpanned, cooling the titanium molds with a splash of water.
The steam hissed loudly, filling the kitchen with a thick fog.
“And my brain is currently focused on ensuring we don’t blow our own arms off during the prototype testing phase.”
I cracked the clay molds open with a hammer.
Three perfectly formed, incredibly lightweight titanium cones rolled onto the table.
They were still radiating heat, but the surface was completely smooth.
No oxygen embrittlement.
No structural corruption.
They were perfect.
I went to work assembling the first prototype.
My enhanced cognitive speed made the complex mechanical engineering feel entirely effortless.
I spliced the friction fuse.
I secured the cone inside the iron casing.
I wrapped the entire exterior in three thick, reinforcing layers of silver duct tape to ensure the blast pressure didn’t fracture the sides.
In exactly eighteen minutes, a terrifying, heavy, highly illegal explosive weapon sat on the oak table.
It looked like a massive, metallic spearhead attached to a thick iron pipe.
“We call it the Thunder Spear,” I announced coldly.
“Because it is going to bring absolute ruin to anyone who stands in our way.”
“I want to touch it,” Hange whispered, reaching out a trembling hand.
“If you drop it, it will detonate with enough force to level this entire wing of the castle,” I warned her, slapping her hand away.
The heavy wooden door to the kitchen suddenly swung open.
Captain Levi walked into the room.
He was holding a clean white rag, wiping down the already spotless wooden handle of his broom.
He looked up, his cold grey eyes sweeping over the chaotic scene.
He saw the blazing blast furnace.
He saw the chalk diagrams covering his dining table.
He saw Hange, covered in soot, hyperventilating over a metal pipe.
And he saw me, holding a highly unstable explosive device wrapped in silver tape.
Levi stopped dead in his tracks.
The temperature in the room instantly dropped by ten degrees.
“What,” Levi stated, his voice completely flat, “is that.”
“It is a targeted, armor-piercing kinetic payload, Captain,” I replied evenly, resting my hand on the Thunder Spear.
“It is designed to penetrate biological plating that standard steel cannot.”
Levi stared at the weapon.
He stared at the massive pile of black powder sitting next to it.
His eye twitched violently.
“You built a bomb,” Levi said, his voice dropping to a dangerous whisper.
“In my kitchen.”
“I built a ballistic solution to our tactical deficit,” I corrected him.
“And I built it in the kitchen because the hearth provided optimal thermodynamic airflow for the crucible.”
“I assure you, I kept the blast radius calculations well within the structural safety limits of the castle walls.”
Levi took a slow, deep breath.
He looked like a man who was desperately trying to calculate how many military regulations he was currently violating just by standing in this room.
“I gave you an order to clean,” Levi said coldly.
“I did clean, Captain.
The dining hall is immaculate.”
“I simply optimized my schedule to include advanced weapons manufacturing during my break.”
Before Levi could formulate a threat involving breaking my legs, another voice echoed from the hallway.
“Kai?”
Eren stumbled into the kitchen doorway.
He was rubbing his eyes, looking entirely exhausted.
He still had a small, red bruise on his cheek from where Levi had kicked him in the courtroom.
Eren looked at the roaring furnace.
He looked at Hange.
He looked at the terrifying, duct-taped weapon sitting on the table.
“What is going on in here?” Eren asked, completely bewildered.
“Did you…
did you blow something up again?”
“Not yet, Eren,” I deadpanned, picking up my coffee mug.
“But I highly recommend you stand behind a load-bearing pillar when we test this prototype.”
Eren looked at Levi for help.
Levi just closed his eyes, pinching the bridge of his nose in profound, overwhelming irritation.
“Get this entire mess cleaned up,” Levi ordered, his voice laced with pure exhaustion.
“And if you blow up my castle, brat, I will personally throw you into the Titan forest without your gear.”
Levi turned around and walked out of the kitchen, shutting the door behind him.
Hange immediately grabbed my arm, her eyes shining with manic glee.
“We have to test it!
We have to blow up a tree!”
“Patience, Section Commander,” I sighed, finishing my coffee.
The Minor Focus Serum was still burning bright in my veins.
My mind was already designing the mounting brackets for the ODM harnesses.
The Armored Titan thought he was invincible.
He thought his biological plating made him a god.
He had no idea that a heavily caffeinated, deeply annoyed twelve-year-old mechanic with a Gacha system had just entirely rewritten the rules of engagement.
“Eren,” I called out, tossing him the heavy Thunder Spear prototype.
Eren caught it, stumbling backward under the unexpected weight.
“Don’t drop that,” I warned him coldly.
“It contains enough concentrated kinetic energy to vaporize your torso.”
Eren froze, staring at the metal pipe in his hands in absolute terror.
“Why did you throw it to me?!” Eren shrieked.
“Consider it a tactical trust exercise,” I quipped.
“Now carry it outside.
We have some advanced structural demolition to conduct.”
I walked out of the kitchen, leaving my terrified brother and an overly enthusiastic scientist in my wake.
The apocalypse was still happening.
But for the first time in years, humanity actually had a fighting chance.
And all it took was a little bit of titanium, a lot of black powder, and the miracle of silver tape.