Prolog

Long ago, Althinel was a world blessed with prosperity and happiness.
Its fertile and abundant megacontinent provided a bountiful life for all who lived upon it. Under the protection of the Goddess Althiel, life flourished in harmony, and goodness spread to every corner of the world.

However, fate turned cruel when a war between gods broke out.
Led by Goddess Nyx, her followers launched a brutal invasion of Althinel after she deliberately opened an interdimensional portal connecting Althinel to its twin world, Sathiel—a realm ruled by Nyx herself.

The war engulfed all races of Althinel. United in desperation, the people and the mighty World Dragons fought together against Nyx's legions, including the Black Dragon—the most powerful dragon of Sathiel.

Despite fierce resistance, Althinel ultimately won the war after fifty years of bloody struggle. Yet that victory came at a devastating cost.
Goddess Althiel fell into slumber from the wounds she suffered in battle.

The consequences of the battle shattered the once-whole megacontinent of Althinel.
It fractured into five separate lands, mirroring the pain and destruction the world had endured during the war.

But the tragedy did not end there.
The black poison of the world—residue left by the death of Sathiel's black dragon—still lingered. And without the conscious presence of Goddess Althiel, it could not be fully purified.
Only the World Dragons, Althiel’s loyal servants, possessed the remaining sacred power to contain the corruption’s spread.

Now, Althinel is trapped in an era of uncertainty.
Amid the ruins of war and suffering, hope and courage still survive.

Thousands of years have passed since the battle that shook the world.
Civilization has slowly recovered, though it still dwells in the shadow of that dark past. In a small village called Alterwood, located far west of the Kingdom of Alcestereon, life flows quietly amidst the dense forests. Yet peace is often disturbed by the rising activity of monsters in the region.

Rain drizzled upon the wooden rooftops of Alterwood Village, creating a soft melody that blended with the tranquil evening. In a secluded wooden cabin on the outskirts of the village, a group of adventurers sat together in darkness. The shimmering glow of a magic lamp was the only source of light in the room.

Sean Akihito, a silver-haired young man with a calm presence, sat in the center, his black sword resting across his lap—a silent symbol of hidden strength and resolve.
Beside him stood a warrior clad in armor with a heavy mace, eyes burning with the spirit of adventure. A blonde-haired elf archer quietly scanned the room with sharp, watchful eyes.

“Hey Sean, where’s that guild broker?” the armored man asked nervously, unease creeping into his voice.

“They should be arriving soon,” Sean replied with composed certainty, his sharp eyes piercing the gloom in anticipation.

Moments later, the wooden door creaked open with a thud, allowing dim light from outside to spill into the room.
The guild broker entered with steady steps, holding a mysterious scroll in his hand.

“Is this Sean’s party?” the broker asked, his voice echoing through the quiet cabin.

“That’s right. We’re Sean’s party,” Sean replied firmly, his eyes gleaming sharply toward the guest.

After a brief exchange, the broker carefully handed the scroll to Sean.
“Open it,” whispered the elf with a tone full of anticipation.

Sean cautiously unrolled the scroll and read its contents.
“Hm… It says, ‘Investigate the contamination at the ancient site north of Alterwood,’” he muttered under his breath.

“All right. Let’s move out,” Sean declared with determination, his eyes lighting up with resolve.

With firm resolve, Sean’s party prepared for their new mission.

The clashing of blades echoed through ancient ruins, forming a rhythm of battle that rang through the silent night.
Three brave adventurers stood against a fearsome bull-like monster, ready to face the danger ahead.

“Heaa—Crescentmoon Slash!!” shouted the silver-haired youth, his sword slicing a crescent arc through the air, releasing a dazzling burst of energy.
The monster roared in fury before collapsing under the crushing blow.

“Fuuuh… That takes care of the minotaur,” Sean exhaled in relief, wiping sweat from his brow.
But unease still lingered in the air.

“Hey Yuuta, is this really the right place? It doesn’t seem contaminated to me,” Sean asked, seeking clarity.

“The broker said this is it,” Yuuta confirmed, nodding with confidence.

But doubt crept into their minds.
Shina, ever firm and skeptical, voiced her frustration.
“Hah… Are they messing with us? Instead of giving us useless info, they should be here helping. Bet they’re enjoying warm beds in the capital right now,” she muttered bitterly.

“They’re impossible to understand,” Sean added with a sigh. “And you, Yuuta—taking this mission without question. You should’ve demanded support from HQ through that informant.”

Yuuta stood by his decision.
“He’s just a broker. And we’ve already lost so many to these contaminated monsters. We’re the only ones left in the village. If not us, who else is going to make sure this place is safe?”

“Hah… Do as you please,” Sean said with a hint of frustration. “I’ll follow whatever you think is best. Right, Shina?”

Shina nodded, her expression somber.
“Let’s hope HQ really is tied up, and not just ignoring us…”

Shhh…

Suddenly, the calm turned to tension.
Dark smoke began to rise from the minotaur’s corpse, unsettling the adventurers still catching their breath.

“Uh!?” Yuuta’s face twisted in shock.
“This black smoke… it only appears around contaminated creatures. Don’t tell me…”

Sean narrowed his eyes.
“So… they die first… and then become contamination?” he murmured, piecing together the eerie puzzle.

But before they could react—

“Shina, get ready,” Yuuta ordered sharply.

“Understood,” she replied calmly, drawing her bow.

Two smaller contaminated minotaurs emerged from behind the fallen one, glowing red eyes filled with menace.
Panic struck the trio as they realized the situation had escalated.

“Uh!? H-Hey Yuuta, this isn’t normal! I’ve never heard of three contaminations in one spot!” Sean said, panic rising in his voice.

“Damn it, you’re right. This is bad,” Yuuta growled, tense.

Without further warning, the monsters attacked.
Roars thundered through the air, plunging the ruins into chaos.

“Let’s go, Sean! Shina!” Yuuta shouted, rallying them.

Sean drew his sword.
Shina fired her arrows with precision.
Yuuta charged forward with his shield glowing with power.

The clash began.

Roars shook the air as the trio battled fiercely.
A sudden kick sent Yuuta flying across the ruins, pain surging through him, but he gritted through it.

“Yuuta’s in trouble…” Sean muttered, eyes narrowing as he moved to draw the monsters’ attention.

Slash!
“Uh!?” Yuuta gasped as a massive axe narrowly missed splitting him in two.

“Yuuta!!” Sean cried out, rushing to his fallen friend.

“Sean, don’t be reckless!” Shina yelled, warning him.

Through grit and breathless determination, they fought on the brink of death.

“HAA!—Heavy Slash!” Sean shouted, his blade tearing through one of the smaller minotaurs, cutting it clean in half.

“Thanks, Sean…” Yuuta said weakly, gratitude in his eyes.

Sean grinned—until—

“SEAN!!”
Yuuta suddenly tackled Sean aside.

“What are y—”
Before Sean could finish, Yuuta’s body was split by a brutal axe strike.

“Yuuta…!”
“Sean, snap out of it!” Shina shouted, drawing her bow.

Sean’s heart thudded as reality set in.

“ROAR!!”
The remaining minotaurs roared again, ready to finish them off.

“Damn it, Yuuta… I’ll avenge you,” Sean growled, gripping his sword tightly.

“I’m out of arrows!” Shina shouted, panic lacing her voice.

Grab—
“Damn…!” Shina gasped as a minotaur caught her leg and slammed her into the ground, then stomped on her mercilessly.

“SHINA!!”

Boom! Thud! Crash!

Sean himself was flung back by a vicious kick, landing amidst the shattered ruins.

Lying amidst rubble and despair, something dark stirred within Sean.

“No… I promised Yuuta… those who survive must avenge us—
Against those who abandoned us… and the ones behind it all…”

BOOM!!

“GRRHH!!”
The two remaining minotaurs were blasted back by a surge of red energy as wind erupted outward.

Sean’s hair turned crimson.
His aura blazed like fire.
Eyes glowing with wrath.

“You bastards… I, Sean Akihito, will make you PAY!!” he roared.

The final crash faded.

The scent of blood and ash filled the air.

Sean’s body lay motionless on the cracked ground, unconscious.
The dark power within him had burned out, leaving only scorched earth and smoldering wounds.

Silence.

Until—
The soft sound of footsteps.

Someone emerged from the mist.

Their movements were silent.
They wore a long, black hooded cloak that concealed their face, only the faint outline of their chin and lips visible.
The hem of the cloak was tattered, but the fabric pulsed with ancient magic.
On their chest: the emblem of “Seven Swords encircling a Cracked Crystal.”

They stepped toward a faintly pulsating black crystal shard embedded in the ground.
It radiated the lingering aura of a dark dragon.

(In their thoughts, calm and flat voice)
“Resonance residue is strong. Target shows high affinity. Contamination has reached initial activation threshold.”

They pulled a thin metal tube from their belt.
With gloved hands, they carefully touched the crystal and slid it into the tube, which sealed itself with containment magic.

“…Second fragment secured. Eight remain.”

The figure turned briefly to glance at Sean.

“…Still alive, huh.”

Without another word, the figure stepped back into the fog.

And vanished.

No one would ever know they had been there.