I Built a Safe Zone in the Dead World

Smoke drifted through shattered buildings while infected corpses covered the flooded streets from every direction. Fire reflected across the water-covered roads beneath flashing military lights while distant screams echoed through the storm.

But nobody focused on the battlefield anymore.

Because the city itself had opened.

The massive underground platform continued rising slowly through cracked streets and collapsing concrete while rusted steel groaned beneath the rainstorm. Ancient warning lights flickered across its sides while enormous mechanical pillars emerged from the darkness below the city.

The platform was gigantic.

Far larger than anyone expected.

Like an entire hidden world had existed beneath them all this time.

Yuna stared blankly at the rising structure afterward. "...No."

Silence.

Then she pointed dramatically toward the underground elevator.

"No. Humanity does not get to hide a secret underground civilization while I’ve been sleeping in broken convenience stores."

Reina smirked beside her while resting one blade against her shoulder. "Honestly your priorities impress me."

Akari ignored them completely.

Her eyes remained locked only on Arata.

Because his condition kept worsening.

The black markings had spread farther across his chest and neck now while dark energy flickered around him violently. Rain evaporated faintly near his body while the system continued flashing warnings before his eyes endlessly.

[Synchronization Rate: 78%]

[Warning: Threshold Approaching]

[Emotional Stability Critical]

His breathing remained uneven.

Not from exhaustion.

From pressure.

Because every answer he found only created larger questions.

His father alive, The Creator, Underground civilization, Tyrants, Experiments, And somehow—Everything connected back to him.

Tyrant-01 slowly turned toward the massive elevator platform afterward while rain crashed against its armored body.

"...Path secured."

Then its glowing eyes shifted back toward Arata again.

"...Original host must descend."

Lucien’s golden eyes narrowed immediately afterward. "That won’t happen."

Black energy exploded around him violently while several sharp constructs formed beside him instantly.

But before he attacked—Ren calmly stepped forward.

"...Enough, Lucien."

The battlefield pressure intensified instantly.

Black energy spread around Ren silently while Eden operatives repositioned across the flooded streets. Their silver weapons activated simultaneously with low mechanical sounds while military forces cautiously backed away from both factions.

Even Elena looked tense now.

Because honestly—The battlefield had become something far beyond ordinary survival anymore.

Humans weren’t fighting zombies now, Evolution itself had divided humanity apart.

Lucien quietly smiled afterward despite the tension.

"...You think Eden can control him?"

Ren’s expression remained cold. "Better than Black Flag."

"Arrogant answer."

"Accurate answer."

Yuna slowly looked between both men afterward. "...Do powerful people naturally become dramatic?"

Kaede calmly answered beside her. "...Statistically probable."

"That’s not comforting."

Meanwhile Arata continued staring toward the elevator platform silently.

Something about it felt familiar, Wrongly familiar.

Like his body recognized it before his mind could.

The system flickered again.

[Access Recognition Confirmed]

Pain suddenly exploded through his head afterward, More memories surfaced instantly.

Young Arata inside a laboratory hallway.

His father kneeling before him with exhausted eyes.

"Never go underground, Arata."

Then alarms, Gunfire, Scientists screaming.

Another memory immediately followed afterward.

A giant underground city filled with artificial lights, Children connected to strange machines, One little boy crying inside a containment chamber while black markings spread across his skin.

Then his father shouting again:

"Stop the synchronization trials!"

Arata staggered violently afterward while holding his head.

Akari instantly caught him before he collapsed.

"Arata!"

His breathing became unstable.

"...I remember pieces..."

Her worried expression softened slightly. "What did you see?"

Before he answered— Lucien suddenly spoke quietly from across the battlefield.

"Dr. Hayato Kazuki created the synchronization system." Silence spread instantly.

Even Ren looked toward him afterward.

Lucien calmly continued while rain fell around him.

"He believed humanity could evolve beyond extinction." His golden eyes shifted toward Arata. "Your father wasn’t trying to create monsters." A small pause followed. "He was trying to save humanity."

Tyrant-01 suddenly growled violently afterward.

"...Lies."

Lucien ignored it completely.

"The apocalypse began after governments weaponized his research." His expression darkened slightly afterward. "Black Flag, Eden, military divisions... all of them fought for control over synchronization technology."

Elena’s eyes narrowed. "...That’s not the full story."

"Of course not."

Then Lucien’s gaze returned toward Arata again.

"Your father disappeared after destroying the original facility." Silence followed briefly. "But apparently..." A faint smile appeared afterward. "...he survived."

Arata’s heartbeat pounded painfully.

Because deep down— Part of him wanted it to be true, Even after everything.

Even after the lies and experiments and horror— He still wanted his father alive.

Akari quietly noticed his expression.Then gently squeezed his hand again.Warmth spread through him immediately.

And honestly— That warmth scared him too.

Because every time she touched him— The darkness weakened.

Like the system itself hated losing control over him. Ren observed that silently afterward.

Then quietly muttered, "The synchronization is adapting around emotional dependency."

Akari instantly looked annoyed again. "...Can people stop scientifically explaining my existence?"

Unexpectedly— One Eden operative nearby quietly answered:

"...No."

Yuna pointed dramatically afterward. "SEE? THIS IS WHY NOBODY LIKES SCIENTISTS."

Meanwhile the massive underground platform finally stopped rising.

A giant entrance had opened beneath the city.

Darkness stretched endlessly downward below flickering industrial lights. Ancient steel walls descended deep underground while massive elevators moved somewhere far beneath the surface.

Cold air slowly rose from below.

Not ruined air.

Clean air.

Real civilization air.

Everyone noticed immediately.

Yuna stared blankly. "...They have ventilation too?"

Reina grinned slightly. "You’re really focused on strange details."

"Because I suffered emotionally up here!"

Suddenly— The ground shook again, But this time— Not from the platform, but Something else, Something huge moving beneath the underground city.

Even Tyrant-01 slowly turned afterward.Ren’s expression hardened immediately.

"...Impossible."

Then through the darkness below— A deep roar echoed upward from underground.

Not infected, Not human, Something far worse.

The sound alone made nearby soldiers freeze instinctively.

Yuna’s face lost color instantly. "...Why is there always something bigger?"

Kaede quietly gripped another arrow tighter. "...Unknown lifeform detected."

Lucien slowly smiled afterward.

"...So Eden failed containment too."

Ren immediately looked toward him sharply. "You knew?"

"Only rumors."

The underground roar echoed again afterward, Closer this time, And suddenly—bEmergency red lights activated across the giant platform.

Warning sirens echoed from below the city while automated voices repeated mechanically:

"Containment breach detected."

"Containment breach detected."

Everyone froze.

Then multiple Eden operatives instantly moved toward defensive positions around the elevator entrance.

The white-haired Eden woman spoke rapidly into communication devices afterward. "Seal lower sectors immediately!"

Ren’s calm expression had disappeared completely now.

"...How did it awaken?"

Tyrant-01 slowly stepped backward afterward.

For the first time— The giant armored monster looked cautious, Then quietly it spoke:

"...Alpha has awakened."

Silence.

Absolute silence.

The system exploded violently before Arata’s vision.

[WARNING]

[ALPHA ENTITY DETECTED]

[Original Synchronization Source Identified]

His heartbeat stopped.

Original synchronization source.

Meaning— Whatever existed underground—

Was the beginning, The true beginning.

Akari immediately looked toward Arata afterward as black energy erupted around his body again violently.

The markings spread farther.

79%.

Too close.

Way too close.

Arata gritted his teeth painfully while holding his head.

Voices echoed inside his mind now, Screams.

Laboratory alarms, His father shouting desperately:

"Run!"

Then another unfamiliar voice calmly answering:

"You cannot stop evolution anymore."

Pain exploded harder afterward, Akari grabbed him immediately. "Arata!"

His breathing became unstable again, The darkness around him intensified.

Rainwater evaporated violently around his feet.

And suddenly— The little girl from earlier slowly stepped beside him again, Despite the terrifying energy, Despite the battlefield.

She carefully grabbed part of his sleeve.

"...Big brother..."

Arata slowly looked downward.

Her small frightened eyes stared up at him.

"...You promised."

Silence.

Then something incredible happened.

The black energy weakened slightly again.

Not completely.

But enough.

Ren noticed instantly.

Lucien noticed too.

Even Elena stared briefly afterward.

Because somehow—Human connection itself stabilized synchronization.

Not power.

Not technology.

Emotion.

The realization silently changed everything.

Lucien’s smile slowly faded afterward.

"...That complicates things."

Meanwhile the underground roar echoed again.

Louder.

Closer.

Then suddenly—Something massive slammed against the walls beneath the platform.

BOOOOOOOOM!!

The entire city shook violently.

Screams echoed from lower levels underground.

One Eden operative suddenly shouted in panic afterward:

"Sector gates breached!"

Ren’s expression hardened instantly.

Then finally—He looked directly toward Arata.

"...If Alpha reaches the surface, humanity ends."

Silence.

Rain continued falling heavily around the ruined city while thunder exploded overhead.

Arata stared toward the darkness below afterward.

Because somehow—He already knew.

Whatever waited underground—Was connected to him more than anyone else.

The system flickered violently again.

Then suddenly—A new message appeared before his eyes.

[Primary Host Proximity Confirmed]

[Synchronization Origin Awaiting Return]

Arata froze instantly.

Primary host.

Not him.

Something else existed before him.

Something stronger.

Older.

The real first synchronization user.

Then the voice echoed again from below the city.

Not through speakers.

Inside his mind.

Soft.

Distorted.

Ancient.

"...Arata..."

His blood ran cold instantly.Because he recognized that voice. It was His father voice .

Akari immediately noticed his expression changing again. "What happened?"

Arata slowly looked toward the underground darkness afterward, Then quietly answered, "...He’s calling me."

Silence consumed the battlefield instantly.

And far below the ruined world— Something ancient finally awakened completely.