Far in the north, beyond the barren mountains that have never been fully touched by sunlight, there lies a valley that is not recorded on any map.
The valley is not silent.
It is only… waiting.
A thin silver mist hangs low, blanketing cracked ground filled with the remnants of ancient ruins. Black stone pillars rise like giant gravestones, planted in a circle around a vast crater at the center of the valley. From the depths of that crater, a dim light pulses slowly—like the heartbeat of a giant deep within the earth.
Mana in that place does not flow.
It settles.
And there… something has been born.
Upon a stone altar carved with ancient symbols stands a tall figure. Its skin is pale like moon ash, with black lines forming patterns like cracks across its entire body. Its hair is long, dull silver, falling past its shoulders.
A pair of curved horns grow from its temples—not large, but sharp and elegant like a natural crown.
Its eyes slowly open.
The irises are blood red.
Without pupils.
Without emotion.
Yet every creature who looks upon it feels the same thing—
the instinct to kneel.
It is a Demon King who has long been known to this world, an entity whose rebirth is greatly feared across the land.
A low rumble echoes from the sky as the figure steps down from the altar. The ground beneath its feet does not crack.
Instead—
it darkens.
Before it, tens of thousands of creatures wait in silence. Lines of monsters with scaled bodies and claws as sharp as blades. Horned demons with their wings folded politely. Undead clad in rusted armor standing without breath. Giants as tall as watchtowers. And in the sky, wyvern riders circle above, their wings tearing through the mist.
Their number is not small.
One hundred thousand.
And that is only the beginning.
A demon in a long robe steps forward and kneels.
"Your Majesty Thanatos," he says in a deep voice, "the northern army is ready. The route toward the human settlements along the border is not heavily guarded. The nearest kingdom is still recovering from the dragon incident."
Thanatos: ArchDemon – Demon King of the Death
Thanatos tilts his head slightly.
"Dragons…" he murmurs quietly. His voice is not loud, yet it echoes through the air like a sound rising from the depths of an abyss.
"Creatures born after me… yet they still believe themselves rulers of the sky."
He raises his right hand. A glowing map forms in the air—displaying human territories, fortresses, cities, and supply routes.
"Attack the northern mining region," he says calmly.
"We will take that mine."
Several monster commanders exchange glances.
"Let them taste fear before destruction. Destroy the smaller settlements first. Cut off their trade routes. Let the news spread faster than my army."
A faint smile forms on his lips.
It is not a smile of joy.
It is the smile of an experiment.
"Once again, we will shake this world and make Humanity know the pain," he says with a dark laugh.
A giant kneels with a thunderous sound.
"Your command, Your Majesty"
Thanatos gazes toward the mist-covered horizon.
"I have been reborn in this world," he says flatly.
"And this world will remember who its first owner was."
The sky above the valley begins to darken.
Fifty thousand troops move at once, while the rest remain behind.
The undead march without sound.
Monsters growl low.
Wyvern riders ascend into the sky, cutting through the clouds.
The invasion is not announced.
It begins.
And far away—
some people begin to feel a cold that should not exist.
Something older than history…
has awakened.
____
Eisenvald — The Northern Frontier City
The wind that blows through the mining city of Eisenvald always carries two scents that never disappear—hot iron and stone dust.
The city stands along the slopes of the northern mountains, surrounded by steep cliffs rising like natural walls. Below lies a massive open pit mine yawning into darkness, resembling an old wound that never heals.
Eisenvald's buildings are made of gray stone and black wood hardened by time. Not beautiful, but sturdy. Tall chimneys release thin smoke even when night has fully fallen.
This is not a grand trade city like the port cities in the east.
But Eisenvald possesses something far more valuable.
Mines.
The veins of rare metals buried within the mountains make this city one of the strategic points of the Kingdom of Etravia. That is why the stone walls are built high, the gates reinforced with thick iron, and a large royal garrison is stationed here.
Eisenvald may not be a wealthy city.
But it is not a city that can be easily taken.
At least… that is what they have always believed.
That night feels different.
The sky is too dark.
The wind is too cold.
A guard stands at the northern watchtower, staring into the mist-covered valley.
He frowns.
"Why is it so quiet…?"
Usually at this hour the sound of night insects can still be heard. Sometimes the howls of mountain wolves echo from the distance.
But tonight—
there is nothing.
No sound.
No life.
As if nature itself is holding its breath.
Then—
the ground trembles.
At first it is subtle.
So subtle it is almost unnoticeable.
But a few seconds later the tremor returns.
Stronger.
Heavier.
DUM…
The guard straightens.
DUM… DUM…
Not one step.
Not two.
It is the sound of thousands of footsteps striking the earth at the same time.
His eyes widen.
Behind the thick northern mist—the wild lands beyond the kingdom's border—shadows begin to appear.
One.
Ten.
A hundred.
Then… thousands.
The creatures emerge from the fog like a nightmare slowly becoming real.
Scaled monsters crawl forward with glowing yellow eyes.
Undead in rusted armor walk silently, their empty eye sockets emitting pale green light.
Giants the size of houses step forward heavily, cracking the earth with every step.
And in the sky—
winged shadows block the moonlight.
Wyvern riders.
The guard swallows hard.
His hands tremble as he grabs the alarm bell.
Then he rings it with all his strength.
CLANG! CLANG! CLANG!
"ATTACK!!"
His voice breaks in panic.
"ATTACK FROM THE NORTH!! MONSTER HORDE!!"
The once-peaceful city of Eisenvald descended into chaos within minutes.
Children's cries erupted from the houses.
Mothers pulled their children inside, locking the doors with trembling hands.
The miners who had just returned from the mines had not even had time to wipe the dust from their faces. Yet without hesitation, they grabbed their pickaxes and mining hammers.
No longer as tools of labor.
But as their final weapons.
The city gates were shut tightly.
Ballistae atop the walls began firing massive bolts toward the approaching monster army.
WHOOSH!
One bolt struck the chest of a large reptilian monster and buried itself deep within its body.
The creature collapsed.
But the line behind it did not slow down.
They kept advancing.
Like a black tide that could not be stopped.
Then the giants moved forward.
They carried enormous tree trunks used as battering rams.
Their steps shook the ground.
BOOM!!
The giant trunk slammed into the city's iron gate.
The entire wall trembled.
Soldiers atop the wall nearly lost their balance.
"The gate is strong!" a captain shouted.
"Keep firing!"
Arrows and ballista bolts rained down upon the giants.
Some fell with terrifying roars.
But there were still too many left.
The second strike came.
BOOOOM!!
The iron gate that should have been able to withstand an army of humans began to bend.
A soldier in the watchtower stared in disbelief.
"No way…"
His face turned pale.
"That iron gate… cracked?!"
He did not have time to say anything more.
WHIST—
A black arrow pierced his throat.
The arrow came from the line of Skeleton Archers outside the wall.
The soldier staggered.
Then fell from the tower.
His body struck the ground like a broken doll.
While the guards focused their attention on the gate—
another shadow had already moved.
On the darker side of the wall, several slender figures climbed the stone with terrifying speed.
Devil Assassins.
Their bodies were thin, their skin blackish like smoke. Their red eyes glowed in the darkness.
Within seconds they were already on top of the wall.
"—Huh?"
One soldier didn't even have time to raise his sword.
A black sickle flashed.
His head separated from his body.
Blood splattered across the stone wall.
Another Devil Assassin immediately turned the gate pulley from inside.
The iron chains moved.
CLANK… CLANK…
The gate slowly opened.
And at that moment—
the gates of Eisenvald fell.
The wave of monsters surged in like a black flood.
Terrifying roars shook the city.
Undead rushed through the stone streets.
Scaled monsters tore open house doors.
Wyvern riders dived from the sky, snatching soldiers from the walls.
Human screams filled the night air.
A small child stood in the middle of the road, crying.
"Mother…?"
But his mother lay not far from him.
Not moving.
Blood flowed across the stone road.
That night—
Eisenvald was no longer a mining city.
It became a slaughterfield.
"Hold the line! Don't fall back!!"
A guard captain slashed down a small demon that leapt toward him. Black blood splashed across his face. Beside him, a comrade collapsed with an undead spear piercing his chest.
Fires began to spread.
Wooden houses burned as wyvern riders dropped fireballs from the sky.
Screams.
The smell of burning flesh.
The sound of steel clashing against claws.
A giant grabbed a guard and hurled him into a stone wall—his body shattered before it even touched the ground.
A flash of silver light split the night.
A glowing sword cut the undead into ash with a single swing.
A woman stood between the child and the darkness.
Her hair was long, pale silver, fluttering in the hot wind of the flames. Her white armor was stained with blood and soot, yet the holy symbol on her chest still shone brightly.
Seraphina Noctrelle.
A half-vampire Imperial Hero and a blessed Holy Knight.
"Take that child to the back!" she ordered one of her companions.
Two members of her party stood at her sides—
a mage in a dark blue robe with a spinning magic circle behind him, and an elf archer in a firing stance with a glowing arrow nocked to his bow.
They had only entered the city of Eisenvald this afternoon to search for information about someone. But who could have predicted a monster raid would happen tonight?
"What is this…?" the mage murmured, his face pale.
"Their numbers don't make any sense…"
Seraphina tightened her grip on her sword.
The sky above the city was filled with wyverns.
The ground was filled with monsters.
This was not a random attack.
It was an organized invasion.
And only one being could command an army this large.
"The Demon King…" she whispered.
Her eyes burned with holy light.
"So you're the one behind all of this."
Her thoughts drifted to the reports about the incident in the city of Ashen—the rain from the abyss, the mysterious destruction, and the unnatural aura of darkness.
That Black Rain.
She had thought it was an anomaly.
Now she knew.
"That was your doing as well… wasn't it?"
Without waiting for an answer, she leapt into the battlefield.
Holy light exploded from her body, sweeping away the first wave of monsters within a wide radius.
But there were too many.
Fifty thousand was not a number that a single hero could stop.
That night, Seraphina was not searching for Hax.
She was trapped in a war far greater.
And in the distance—
from behind the northern mist—
a pair of red eyes without pupils watched the burning of Eisenvald.
Without emotion.
Without hesitation.
The first experiment…
was proceeding exactly as planned.
Flames had spread all the way to the center of the city.
The defensive walls had partially collapsed. Blood flowed between the cracks of the stone streets, mixed with ash and charred wood fragments. Cries for help were slowly turning into desperate groans.
And in the middle of the inferno—
a pressure of mana descended like a giant hammer.
The monsters at the front line suddenly stepped aside.
They made way.
Seraphina felt the change even before her enemy appeared.
The air shifted.
Heavier.
Denser.
And most disturbing of all—more orderly.
The waves of mana that had been chaotic from battle suddenly flowed like a river directed toward a single center of power.
Seraphina lifted her head.
Her eyes pierced through the black smoke filling the streets.
Then…
something emerged from the mist of war.
Heavy footsteps echoed over the cracked stone road.
The figure was tall. Not as massive as the giants that had smashed the gate earlier, but its posture still towered nearly twice the height of an ordinary human. Its body was covered in dull black armor filled with scars of countless battles.
Two thick, curved horns grew from its head.
Its face—
the head of a bull.
A Minotaur.
Hot breath escaped from its nostrils, visible like steam in the cold night air.
In its hand it held a gigantic war axe. The blade emitted a dark purple glow that pulsed slowly, as if it possessed a life of its own.
The creature stopped several meters before Seraphina.
The aura coming from it pressed down on the surrounding air.
Even the flames burning the nearby houses seemed to tremble smaller.
"I am General Valtherion."
His voice was deep and heavy, like a massive stone dragged across iron.
"Commander of the Demon King's army on the northern front."
His dark red eyes stared directly at Seraphina.
"Hero of the Empire… your presence has been accounted for."
Seraphina did not answer immediately.
She simply raised her sword.
The silver blade emitted a gentle yet sharp holy light, cutting through the black smoke like dawn piercing the night.
"I have accounted for one thing as well," she finally said.
Her voice was cold.
Calm.
"I will not allow you to advance any further."
For a fraction of a second—
both stood still.
Then the ground exploded.
Valtherion vanished from where he stood.
His speed was far too fast for a body that size.
Seraphina barely had time to raise her sword.
DENTAAANG!!
The crash of metal shook the entire street.
Valtherion's gigantic axe slammed into Seraphina's holy sword with terrifying force. The shockwave swept through the surrounding buildings.
Windows shattered.
The walls of already damaged houses collapsed even further.
Seraphina was pushed back several steps, her heels scraping across the stone road.
Her eyes narrowed.
Strong.
Far too strong for an ordinary commander.
Valtherion raised his axe again without giving Seraphina time to breathe.
The second attack came from the side—fast, brutal, and deadly.
Seraphina twisted her body.
"Divine Skill: Holy Shield!"
Holy light instantly formed a semicircular barrier in the air.
The giant axe struck it.
CRACK!
Cracks spread across the shield's surface like glass struck by a hammer.
The shield nearly shattered in a single blow.
But it was enough—
enough to open a narrow opportunity.
Seraphina stepped forward.
"Divine Skill: Sword of Light!"
Her body shot forward like lightning.
Her sword pierced the narrow gap between the plates of Valtherion's armor.
Holy light exploded from within.
A burst of white energy swept away the darkness of the burning street.
Valtherion stepped back half a step.
Thick black blood dripped from the opening in his chest.
Yet—
instead of anger,
he laughed.
A heavy laugh echoing between the burning houses.
"Beautiful light…" he murmured.
"But light has never saved the world."
His glowing red eyes stared at Seraphina without blinking.
"Light… only delays the darkness."
Valtherion raised his axe high into the air.
The muscles in his arms tensed like living steel.
Then—
he slammed it into the ground.
"Axe Skill: Doom Blast!"
Glowing red cracks spread from the impact point, crawling across the ground like a giant spiderweb.
A surge of heat erupted in every direction—
and then—
BOOOOM!!
The ground around them exploded.
The stone street lifted and shattered into fragments.
The battlefield transformed into a massive crater spewing red magma from the earth's fractures.
A wave of heat blasted outward.
The mage standing behind Seraphina was thrown away by the explosion.
"Ghh—!"
His body slammed hard into a stone wall before falling to the ground.
The archer at Seraphina's side was also thrown away.
She rolled across the scorching ground while her bow snapped in half.
Seraphina gasped.
Her breathing grew heavy.
Since being appointed as the Empire's Hero, she had faced many monsters.
She had completed dozens of extermination missions.
She had slain ogres, wyverns, even high-ranking demons.
But an enemy like this—
was different.
This was not merely a powerful monster.
This was a Demon King's General.
A creature standing at the peak of the army of darkness.
And Seraphina knew one bitter truth.
She was not the hero who defeated the Demon King hundreds of years ago.
She was merely the successor to that title.
The successor to a legend far too large for one human to carry.
Her fingers tightened around the sword's hilt.
She could win.
She believed that.
But that victory—
would not come without a price.
And the price she would have to pay…
was time.
While she fought here—
the city of Eisenvald continued sinking into hell.
Human screams still echoed from the burning alleys.
Monsters ran between collapsing houses.
The sky was filled with wyvern shadows circling like carrion birds.
And with every passing second—
more lives were lost.
(Translation continues exactly following the narrative…)
When Seraphina finally raised her sword and declared:
"Divine Skill: SANCTUARY."
A dome of holy light formed, protecting the survivors while draining her mana.
Outside the barrier, Valtherion watched calmly and struck the dome with his axe.
No cracks appeared.
The barrier held.
"How long can you hold it, Hero?"
He smiled faintly.
"Ten minutes? Five?"
Or perhaps…
only a few seconds more.
And at that moment—
far in the northern sky—
something began to move.
The wind changed direction.
Dark clouds split apart as a black shadow cut rapidly through them.
Something—
was approaching.
____
Night in the city of Liora felt far too quiet.
The wind blew gently across the rooftops, carrying the scent of wood and damp soil. Ever since the comet fragment incident he had created, the city had grown even quieter than before.
But for Hax—
the world was never truly silent.
He stood atop the tallest building in the city, his black armor reflecting the pale moonlight.
His helmet faced north.
Then—
a mechanical voice echoed inside his consciousness.
[Warning.]
[Abnormal Mana Distortion Detected.]
[Source Classification: Unknown.]
[Threat Level Reassessment in Progress…]
A thin red light flickered in the corner of his system view.
Hax did not move.
The wave was far away.
But unmistakable.
Not merely a large mana release.
It was organized.
Centralized.
Alive.
[Analysis Complete.]
[Entity Signature: Comparable to Former Demon King-Class.]
[Probability of "Arch Demon-Type Entity": 72.4%]
[Location: Northern Region]
Hax narrowed his gaze behind the helmet.
"So… it finally appeared."
This was not residual energy.
Not a failed experiment.
Not a wild monster.
This was the core.
The source.
And the waves continued spreading—accompanied by thousands of smaller mana fluctuations around it.
A large-scale monster raid and the emergence of this world's Demon King.
The city in the north…
would not survive.
Light footsteps sounded behind him.
"Master Hax…"
Lyra stood several meters behind him, her long hair moving gently in the night wind.
Her unique body—a fusion between a Dryad and a new sprout of life—was never something she hid from her master.
She was proud.
That power had been granted directly by Hax.
And with that new body she could also feel the terrifying mana waves in the distance, though not as clearly as Hax's system detection.
"Did something happen?" she asked softly.
Hax did not answer immediately.
He looked at the dark horizon.
The decision had already been made before the question was asked.
"I'm leaving," he said briefly.
Lyra fell silent for a moment.
"Leaving… where?"
Silence.
Hax never explained his destination.
Never gave long plans.
But this time, something in his voice was different.
"The situation will become more dangerous," he said flatly.
"This wave is not a coincidence."
Lyra clenched her hands.
"Is this… the Demon King?"
Hax did not answer.
Instead, he turned slightly—just enough for the shadow of his helmet to cover Lyra's face.
"Protect this city."
His voice was not loud.
But absolute.
"You are Liora's first line of defense."
Lyra's eyes widened.
She wanted to say something.
To stop him.
To ask more.
But she knew—
once Hax had decided, nothing could stop him.
"…Understood, Master Hax," she finally replied, though a faint tremor lingered in her voice.
[Aero Skill: Fly.]
Dense black mana enveloped Hax's body.
The air around him vibrated, then burst softly as he lifted from the rooftop.
There was no holy light.
No magnificent effect.
Only a heavy pressure that cracked the roof tiles beneath him.
Lyra looked up as the black-armored figure shot into the night sky—
toward the north.
Toward the center of destruction.
The farther he flew—
the clearer the pressure became.
The sky in the distance glowed faint red.
Smoke.
Fire.
And in the middle of it all—
a single source of mana standing upright like a pillar piercing the heavens.
[Distance to Epicenter: 34.2 km… 28.7 km…]
Hax accelerated.
The wind tore at his shadow cloak.
His eyes remained fixed on a single point.
"A real Demon King, huh…"
There was no fear in his voice.
No anger either.
Only cold curiosity.
"If you're truly the original owner of that title…"
The mana around him began to darken.
"Don't disappoint me."
And far in the north—
the flames of Eisenvald still burned.