Morning arrived beneath a sky veiled in silver mist.
The Heavenly Flow Sect was unusually quiet.
Even the wind seemed to move cautiously, as if aware that something significant was about to occur.
At the deepest part of the sect stood a forbidden area sealed by ancient formations — a place where ordinary disciples were never allowed to approach.
The Shadow Refinement Chamber.
A massive stone gate towered before Seo Joon, covered in countless engraved runes that pulsed faintly like living veins. The symbols shifted slowly, as if breathing, radiating an ancient and oppressive aura.
This was not merely a training ground.
It was a prison for the soul.
Seol Ah stood beside him, her expression calm but her eyes heavy with concern.
"Once you enter," she said quietly, "no one can interfere. The chamber reflects your heart. If your will falters, the shadows will consume you."
Seo Joon nodded.
He understood.
This was not a battle against an enemy.
This was a battle against himself.
The sect master and several elders stood behind them. Their combined presence weighed upon the surroundings like mountains.
"Remember," the sect master said, his voice steady yet cold, "the Abyss feeds on weakness. Do not reject it blindly — understand it, dominate it, and make it submit."
Seo Joon bowed deeply.
"I will not fail."
The ancient gate slowly opened.
A cold, endless darkness waited beyond.
No light.
No sound.
Only silence.
Seo Joon stepped forward.
The moment he crossed the threshold, the gate shut behind him with a thunderous roar.
Darkness swallowed everything.
Seo Joon could no longer see his own hands. Even his spiritual senses seemed suppressed. The world around him felt hollow, like an endless void.
Then—
A heartbeat echoed.
Thump.
Thump.
Thump.
The sound came from everywhere.
From nowhere.
From inside him.
The Abyssal Heart responded immediately, pulsing violently as if greeting its home.
A chilling voice whispered through the darkness.
"You have returned…"
The ground beneath Seo Joon's feet transformed.
The void shattered like glass, revealing a new world.
He stood within a ruined landscape filled with broken memories.
A cold alley.
A starving child.
A lonely figure abandoned by all.
It was his past.
Young Seo Joon appeared before him — thin, weak, trembling with hunger and despair. The boy's eyes were empty, filled with silent resentment toward the world.
"You were powerless," the shadow-child whispered.
"You were discarded."
"You hated them."
Dark figures appeared around the child — people who mocked him, rejected him, hurt him.
Rage began rising in Seo Joon's chest.
The Abyssal Heart pulsed harder.
The world around him darkened.
But Seo Joon did not move.
He watched quietly.
"Yes," he admitted.
"I was weak."
The shadows trembled slightly.
"But weakness does not define me."
The illusion cracked.
The world shifted again.
This time, he stood upon a battlefield covered in corpses. Rivers of black energy flowed like poison. Countless enemies lay destroyed by overwhelming power.
At the center stood another Seo Joon.
Cold.
Merciless.
His eyes completely consumed by darkness.
A tyrant.
A monster.
This shadow version looked at him and spoke with his own voice.
"Power solves everything."
"Destroy those who oppose you."
"Abandon emotion. Become absolute."
The tyrant extended a hand.
"Accept the Abyss fully."
Infinite power surged around him.
Tempting.
Overwhelming.
Absolute.
For a brief moment, Seo Joon felt hesitation.
With such strength, no one could hurt him again.
No one could betray him.
No one could stand above him.
The Abyssal Heart beat violently, resonating with the offer.
Then—
A gentle warmth appeared within his memories.
Seol Ah's voice.
Her steady presence.
The moment she stood beside him when he had nothing.
The promise he made to remain human.
Seo Joon's eyes cleared.
"I seek strength," he said calmly.
"But not to destroy everything."
The tyrant's expression twisted.
"Weakness."
"No," Seo Joon replied.
"Choice."
He stepped forward.
Instead of attacking, he placed his hand on the shadow's chest.
"I accept the darkness within me."
"But I am its master."
The illusion shattered violently.
The battlefield collapsed into endless light and darkness swirling together.
The Abyssal Heart within him erupted with power — not wild, not chaotic, but controlled.
For the first time, the energy flowed in perfect harmony with his will.
The whispering voices faded.
The raging storm calmed.
The beast inside him bowed.
Outside the chamber.
The elders watched with tense expressions.
The ancient formations around the gate shook violently, releasing waves of terrifying pressure.
"The Abyss energy is stabilizing…" one elder said in disbelief.
The sect master's eyes narrowed slightly.
"He is not being consumed."
"He is dominating it."
Even Seol Ah looked shocked.
Inside the chamber, the darkness slowly receded.
Seo Joon stood alone in a silent void.
Before him appeared a single black flame floating gently in the air.
A condensed fragment of Abyssal power.
A reward.
A recognition.
A new stage.
When he touched it, the flame merged into his body, and a profound transformation began.
His aura deepened.
His control sharpened.
His connection with the Abyss became absolute.
But at that moment—
Deep within the chamber's core, something ancient stirred.
Far older than the sect.
Far older than the Abyssal Heart.
A sealed consciousness awakened slightly.
It observed Seo Joon with interest.
And for the first time in countless ages…
It smiled.
Outside, the stone gate trembled.
Cracks spread across the ancient runes.
The trial was nearing its end.
But something unexpected had awakened with him.
Something even the sect ancestors had never predicted