Chapter 87 — Toward KEA 0.5
S.C. 1510 — Early January
Foosha Forest — Underground Metallurgy Room
The newly expanded metallurgy chamber smelled like:
warm ash
fired clay
metal dust
and a little bit of Zemo's fur
Honestly?
That was Ren's favorite smell these days.
He stood in front of the upgraded furnace with a determined glint in his eyes.
The chamber wasn't finished yet, but tonight wasn't about comfort.
Tonight was about ambition.
KEA Prototype 0.4 was impressive…
but it still had flaws:
the edge chipped under extreme force
mixed veins weren't uniform
hardness varied unpredictably
temperature control felt like gambling
And Ren didn't like gambling.
He wanted consistency.
Strength.
Precision.
He wanted KEA 0.5.
Zemo sat behind him, eyes shining, tail sweeping dust into mini tornadoes.
---
The New Ores — The Trio of Chaos
Ren crouched beside the ore pile.
"Okay… you three. Let's try to be friends today."
He held up:
Iron-rich ore
—the responsible base metal.
Dark mineral ore
—the "mysterious genius" with violent melting habits.
Striped metallic ore
—the flexible-not-flexible wildcard.
Plus a small jar of enhanced charcoal dust, because why not risk his life a little?
Zemo sniffed the dark mineral and backed up like it owed him money.
Ren chuckled.
"Yeah, yeah. I know. You don't trust anything from that clearing."
Zemo's glare said: Correct.
---
The Alloy Equation — AKA Math That Zemo Hates
Ren drew the formula on the stone floor with charcoal:
70% iron
20% dark mineral
10% striped ore
A whisper of enhanced charcoal dust
Zemo looked at the equation.
Then at Ren.
Then flopped onto the floor dramatically.
Ren flicked his ear playfully.
"Not a math fan? Yeah, me neither."
But ratios were life or death in alloy-making.
One mistake and the entire batch might crack, explode, or—worst case—turn into something Luffy might try to eat.
---
Preparing the Furnace — Turning Up the Sun
Ren layered the furnace:
charcoal → ore → charcoal → dust → ore → charcoal
He lit the kindling.
The flames twisted upward, lively and hungry.
Ren gripped the large bellows.
FWOOOOOOOOOM—
The furnace shook like a beast awakening.
Zemo bolted behind a toolbox.
Ren smirked.
"I didn't even pump that hard yet."
He pumped again.
FWOOOOOOOOOOOOOM—
The temperature skyrocketed.
Orange.
Yellow.
White.
White-hot.
This was the highest, most stable heat he'd ever achieved.
The dark mineral inside…
shifted.
It didn't melt the way iron did.
It softened slowly, glowing in a way that felt almost alive—like molten ink bleeding into fire.
Ren leaned forward.
"There you are… behave for once."
The mineral responded by melting in a steady drip—
plip. plip. plip.
Ren's grin widened.
"Yes. YES. This is it!"
---
The Bloom — A Newborn Metal
After nearly an hour, Ren let the furnace cool with a deep exhale.
The chamber felt quiet.
Heavy.
Expectant.
He opened the lid carefully.
Inside…
sat a gorgeous, dense, dark bloom.
Ren lifted it with tongs.
He nearly dropped it.
"…You're heavier."
He turned it under the lantern light.
fewer mineral veins
smoother color
more uniform texture
little to no slag sticking
His heart thudded.
"This… this is huge."
Zemo wagged his tail, proud of his scientist.
---
Forging — Strike Until It Sings
Ren placed the bloom on the anvil.
He raised his hammer.
CLANG!
The bloom compressed beautifully.
No cracking. No splitting. No weird mineral rebellion.
Ren brightened.
"Good. Good. You're behaving like a proper metal."
Heat again. Hammer again.
CLANG—CLANG—CLANG—
Sweat dripped down his chin. Dust clung to his hair.
But every hit made the alloy more uniform.
More stable.
More… right.
Zemo watched like a tiny fox blacksmith.
---
Quenching — The Moment of Truth
Ren heated the rough blade shape until it glowed bright orange.
He dipped it slowly into the oil.
SSSSSSHHHHHH—!!
Steam blasted upward.
Zemo launched himself behind a barrel.
Ren stayed steady.
The sizzling ended.
He pulled the blade out.
It was—
dark.
smooth.
uniform.
beautiful.
He tapped it gently.
TING—!
A sharp, vibrant ring echoed through the chamber.
Ren whispered:
"…You're stronger than 0.4."
---
Edge Test — Proof of Power
Ren sharpened the blade.
The stone shaved off perfect grains.
Then he tested:
Wood
SHNK—
Clean slice.
Bone
CRACK—
Deep penetration, no damage to blade.
Iron bar
DENT.
Only the iron bent.
Ren blinked.
"…This is the one."
Zemo leaped onto Ren's lap like a tiny furry cheerleader.
Ren laughed breathlessly and hugged him.
"This is KEA Prototype 0.5.
Stable. Strong. Reliable."
Not perfect yet.
Not the final alloy.
But the closest he had ever come.
"This… is the blade that will build our future."
Tools.
Base.
Shelters.
Escape routes.
Ships.
One step closer.
KEA was coming.
---
End of Chapter 87