When Goryeo's warships stopped in the middle of the strait, Hosokawa felt the first flare of dread.
Hosokawa—once lord of Hita—was standing at the harbor shipyard early in the morning.
Age had shortened his sleep.
The hour was still wrapped in fog.
Moisture clung to the planks, and the mooring lines of anchored ships hummed low in the wind.
He stood there looking down at the sea.
At the ships he had gathered.
At the soldiers he had urged onto decks.
At the war that, today, was supposed to repay his grudge.
At first, he didn't feel anything strange.
He saw Goryeo's ships shifting toward the strait and took it for a threat maneuver.
It was a scene he'd watched repeat more than once.
The commanders at the harbor reported it the same way.
"If they come out, we sail out and meet them."
"There aren't many ships."
Hosokawa nodded.
This was Shimonoseki.
A narrow channel.
A friendly port.
A position stocked with friendly ships.
If fighting broke out, he believed this side would be favored.
He calmed the impatient samurai and said,
"Don't rush."
"Load everyone."
"Put more soldiers aboard."
But the sea didn't wait.
When Goryeo's warships stopped in the middle of the strait, Hosokawa felt the first flare of dread.
The current there was fierce.
Their alignment looked alien, almost as if they were drifting—yet holding.
The rowing angles and the spacing between hulls were too refined.
Then fire burst.
A heavy blast tore the sea open.
The air over the harbor split in an instant.
When the first cannonball struck a ship outside the harbor mouth, Hosokawa couldn't immediately comprehend the situation.
The sound was too large.
The fragments scattered too wide.
It felt as if the world itself had collapsed.
At the second blast, a hull lifted and slammed back down.
At the third, it stopped being a ship at all.
"Put out!" Hosokawa shouted. "Out—now!"
"Launch the ships!"
"Meet them and fight!"
Commanders ran.
Soldiers surged.
Lines were cut and oars were grabbed.
But the harbor was narrow, and there were too many ships.
When one tried to go out, another jammed behind it.
The current ran outward, but inside the port the ships obstructed each other.
All the while, the thunder continued.
The cannon didn't merely split ships.
They broke the will of ships.
A vessel that lost its rudder spun.
Oars snapped.
A bow took on water.
Before the fight even truly began, the formation was already unraveling.
Still, the samurai shouted.
"Forward!"
"Just latch on and it's over!"
Hosokawa didn't yet understand how hollow those words were.
When the broken ships began to drift with the tide, he stepped one pace closer to the edge of the pier.
From there, he saw it.
The direction the current pulled.
And waiting at that exact point—Kyushu's ships.
They were aligned like beasts lying in ambush, not anchored, simply waiting.
From that moment on, it wasn't a fight.
Hooks caught drifting hulls.
Arrows poured down.
Those who boarded shoved.
Those shoved fell into the sea.
From far away, Hosokawa watched clearly—
armored bodies sinking into the water.
He could no longer make sound.
This wasn't a fight.
His resolve to repay blood with war was sinking, piece by piece, into the sea.
"Why…"
The sound that leaked from his throat was swallowed by the wind.
He had staked everything.
The rage of losing his domain, his honor, the face of his house.
But the enemy did not treat this battle as a choice.
They waited, bound, and cut away.
In Hosokawa's sight, soldiers still crowded the harbor.
Men who had not yet boarded.
Men who waited for orders and flailed in place.
He could not send them out.
To send them out was to send them into that sea.
Something inside his chest went out.
He had raised a war, yet the fight would not reach his hand.
He had meant to repay his grudge, yet his arm could not touch.
That day, standing on the pier, Hosokawa understood for the first time.
He had begun this war.
And it was already beyond anything he could control.
The battle ended.
When Kyushu's lords returned and stepped onto the docks, every one of them said the same thing.
They wanted to see Goryeo's ships.
More precisely, they wanted to see the cannon.
They wanted to look with their own eyes at the cannon that had carried the battle to victory.
It wasn't entirely unknown.
Dutch merchants had come and gone, and they knew of tools that threw iron lumps.
They had thought: loud, yes, but if it's only hurling stones, there are other means.
But what they'd seen today was different.
Cannons lined in a row along a ship's side.
Boom—boom—
and with every blast enemy ships cracked, split, sank.
It wasn't a fight of ramming to break.
They didn't even need to close.
Just by turning broadside and firing, a formation collapsed.
In that instant, the lords felt it.
The rule of war had changed.
At that, Song I-jeong shook his head.
Don't teach them.
A new weapon like cannon—once you reveal it—returns as a blade.
Park Seong-jin said it plainly.
"If I teach you this, one day you'll use it to strike us."
"In the end, I'd be chopping my own foot."
Ōtomo Yoshimune of Bungo stepped forward.
"We will not betray you."
"Once we swear loyalty—"
His words carried weight.
And he was known as that kind of man.
Park Seong-jin couldn't fully turn away from that gravity.
But he added a condition.
Do not let it spread beyond them.
So a handful of daimyō boarded Goryeo's fast ships.
On deck, their eyes rested on the cannon with a complicated look—
half curiosity, half fear.
Park Seong-jin explained the firing process briefly.
A metal tube.
Powder loaded.
Fire.
No more than that.
He brushed it off as something you could find on Dutch ships as well.
But who were these men.
They could not fail to grasp what it meant—
that the era of boarding and ramming had shifted into an era of opening your flank and firing.
Questions followed.
Park Seong-jin answered that powder was hard to make, and that he'd received support from the Central Plains and Jiangnan.
It was true.
The daimyō nodded.
At least in this land, producing it immediately would be difficult.
Attempts had been made, but the process of producing saltpeter was demanding.
This wasn't something you could copy just by watching once.
They inspected the flat-bottomed fast ships, comforted the troops, and withdrew in silence.
Park Seong-jin issued a final order.
Cannon technology would be strictly controlled.
A force that changes the flow of war—if left uncontrolled—becomes disaster.
When the battle report was delivered, the council hall stirred in an instant.
More than two hundred enemy ships sunk.
That count excluded small craft and tallied only sekibune-class warships.
It was an outcome too large even to call a "result."
Friendly losses were minimal.
Enemy dead could not be calculated precisely.
If each ship carried fifty to a hundred men, then even conservatively it was ten thousand—
and at the high end, twenty thousand.
As the numbers rose and fell, no one could continue speaking easily.
The weight of the battle seemed to settle onto the floor of the hall.
Park Seong-jin called for Nabeshima Motonari.
"Find out how the enemy assesses their own losses."
Motonari nodded and immediately gave an order to the deputy behind him.
The command passed without friction.
Scouts would move and learn.
The damage did not stop at numbers.
Among the ships sunk were several atakebune—
the large vessels that carried lords.
It was highly likely at least three daimyō were dead or gravely wounded.
When that reached the room, the hall went quiet again.
Questions about losses continued, but no one answered readily.
Park Seong-jin continued.
"Confirm whether troops are gathering at other ports."
"Send fast ships and find out."
The instructions were concise, and the meeting settled at that point.
An order went out to comfort the troops.
At the same time, Park Seong-jin quietly checked the remaining powder.
There wasn't much.
It was close to empty.
This fact could not be allowed outside.
They were gathering soil to produce saltpeter locally, but progress was slow and the yield uncertain.
Possibility existed, but the limits were clear—
it could not match the speed the war demanded.
Park Seong-jin calculated in silence.
No matter how he counted it, what he could sustain was close to here.
A battle like this—breaking Japanese ships at sea—
cannon were perfectly suited.
But cannon required powder.
And now powder had to be spared.
It was frustrating.
And again, it was frustrating.