It wasn't just him—Tanjiro, Zenitsu, and Inosuke in the distance all sensed the change at the same time.
The weather had shifted.
The night sky, once veiled only by thin clouds, had gathered thick, ink-black storm clouds.
The superheated updraft created by the Great Dragon Fire Technique had risen rapidly, colliding with cold air at high altitude, forming a massive thundercloud in less than a minute.
Rumble—!
A deep roll of thunder echoed within the clouds.
The air grew heavy as humidity and pressure dropped sharply.
An overwhelming sense of oppression pressed down on everyone present.
"Th-this… what's happening? I can barely breathe…"
Tanjiro clutched his chest, struggling for air.
Zenitsu, sprawled on the ground, trembled violently, his blond hair standing on end from the static filling the air.
As a practitioner of Thunder Breathing, he understood better than anyone what was forming within those dark clouds above.
"N-no… that's impossible…"
His teeth chattered as his eyes locked onto Rin, standing calmly below the storm. His voice trembled with deep, instinctive fear.
"That's not a Breathing Technique… that's true heavenly power! That's the force of nature itself! How could a human possibly control something like that?!"
Amid Zenitsu's collapsing composure, Rin slowly raised his right hand.
Zzzzt—~!
A blinding bolt of lightning ignited in his palm.
Like a trigger, it resonated instantly with the violent lightning gathering within the storm above.
Rumbling!!!
The sky split apart.
Countless thick bolts of lightning intertwined wildly within the dark clouds.
The deafening thunder seemed capable of shattering the entire mountain.
Under everyone's terrified gaze, the lightning began to gather and take form.
An ancient beast, composed entirely of lightning, slowly emerged from the heavens.
It bore the horns of a dragon and the mane of a lion, its massive body covering half the sky above the Swordsmith Village.
Every strand of lightning that made up its form carried destructive power enough to level mountains.
Lightning Release Secret Technique: Kirin.
The moment the lightning beast took shape, the entire village was illuminated as if it were daylight.
A crushing pressure, belonging to nature itself, descended without restraint.
Zohakuten froze in place.
The lightning-based Blood Demon Art he was so proud of was insignificant before this overwhelming force.
He wanted to flee, but the static filling the air locked down the space around him. Even the air he breathed carried a sharp, burning scent of ozone.
"What… kind of monster are you…"
The words barely escaped his throat.
Rin stood high above, his Eternal Mangekyō Sharingan reflecting the storm-filled sky, like a god delivering judgment.
"Have you ever seen true lightning?"
His raised hand suddenly dropped.
"Disappear with it."
Roar—!!!
The Kirin let out a thunderous cry, tearing through the sky as it transformed into a blinding pillar of light that descended at the speed of lightning.
The attack struck in less than a thousandth of a second.
There was no chance to dodge, no room to defend.
The instant Kirin struck the ground, there was no sound.
The explosion had already surpassed the limits of human hearing. All anyone could perceive was a blinding white, as if the world itself had been stripped of color.
Then came the shockwave—an overwhelming force that crushed and erased everything in its path.
Rumbling—!!!
The earth wailed as it collapsed.
Where Zohakuten had stood, everything within a hundred meters—rock, trees, even the underground hot spring veins—was completely vaporized by the devastating lightning.
The blinding light lingered for several seconds before gradually fading.
When Tanjiro and the others finally regained their vision and cautiously peeked out from behind the boulder they had taken cover behind, the sight before them left their minds completely blank.
It was gone.
The once-level ground had become a massive, charred crater over ten meters deep and nearly a hundred meters wide.
At the edges, rocks had been melted by the intense heat into dark red magma, slowly flowing down the slopes.
The air was thick with the stench of burning.
As for Zohakuten—the demon who had stood there with such arrogance—not even a trace remained.
Under that level of destruction, even the regenerative ability of an Upper Rank meant nothing. Every cell had been erased without a trace.
Rin stood at the edge of the crater, slowly lowering his right hand.
A breeze passed, stirring his black haori.
He exhaled lightly, his breathing still steady.
Though Kirin possessed devastating power, it relied on naturally occurring lightning, so the chakra it consumed was actually minimal.
This was precisely why it was called the ultimate Lightning Release secret technique.
"R-Rin-san…"
Tanjiro swallowed hard, his legs unsteady as he walked to the edge of the crater.
Staring at the massive pit that had reshaped the terrain itself, his understanding of power was completely shattered and rebuilt.
No wonder he could call himself a Special Executive Officer.
With strength capable of flattening a mountainside in a single move, even if Muzan sent all the Upper Ranks at once, it would probably just mean calling down a few more bolts of lightning, right?
"Stop zoning out."
Rin's voice pulled Tanjiro back to reality.
He leapt down into the scorched crater and walked toward a pile of debris at its center.
"The decapitation condition for Upper Rank Four is a bit special. That thing just now was only a fragment of emotions. The real body is still hiding."
Rin lifted his boot and casually kicked aside a still-smoking rock.
Beneath it, a tiny old man, no bigger than a rat, curled up with his hands over his head, trembling uncontrollably.
Hantengu's true body—the Cowardice Demon.
Even though he had only been grazed by the edge of Kirin, his tattered clothes had been reduced to ash, and his entire body quivered in terror.
"P-please… don't kill this old man… I'm so pitiful, so weak… why must you drive me to death…"
Even now, Hantengu spoke in the most groveling tone, uttering the most twisted words.
"Poor and weak?"
Rin looked down at the wretched creature at his feet.
"When your clone called you that earlier, it made me sick. You've slaughtered so many people, yet you still pretend to be a victim. A soul as filthy as yours doesn't deserve to exist—even being burned to ash is too kind for you."
Zing!
The Kusanagi sword slid half an inch from its sheath, a cold flash of steel cutting through the night.
Before a scream could even form, the walnut-sized head was cleanly severed from the body.
With the death of the main body, the overwhelming demonic presence that had blanketed the Swordsmith Village receded like a falling tide, vanishing completely.
[Ding! Detected host has slain one of the Twelve Kizuki—Upper Rank Four, Hantengu!]
[Perfect execution achieved with Lightning Release Secret Technique: Kirin. Absolute power dominated the battlefield!]
[Congratulations! You have obtained 12,000 dimension points!]
The system's notification sounded promptly in his mind.
Rin sheathed the Kusanagi sword and looked toward the far side of the village.
At the very moment Hantengu died, a series of sharp sounds—air splitting and water splashing—suddenly echoed from the direction of the swordsmith workshops.
"Let's go. Time to check how Muichiro's side is doing."
Rin turned and gestured to Tanjiro and the other two, who were still frozen at the edge of the crater.
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12 Advance chapters:Patreon/slept01