The air was heavy—so heavy that even breathing felt like swallowing molten iron.
"Master Kuro… what is happening?!" one of the onlookers whispered, his voice quivering. "Who is releasing so much power? Is it Yume?"
Murmurs spread like wildfire. People exchanged terrified glances, unsure whether to run or drop to their knees in fear.
But then all eyes turned—not to Yume, not to Master Kuro—but to Ren.
He stood in the center of the training ground, his black hair whipping wildly as his aura blazed around him like a living storm. The earth cracked beneath his feet, shadowy fissures spreading out like a spider's web. His chest rose and fell with each breath, every exhale radiating heat and darkness.
"How much power does he have?" someone shouted over the rumbling ground. "Even an S-Rank—and even Master Kuro—can't stop him!"
It was as if the whole world had suddenly remembered to be afraid of Ren.
Zen stood frozen, a bead of sweat tracing down his face as he stared at the impossible.
That can't be real… he thought, his mind spiraling. No one should have that kind of strength. If he has this power now, what will he become later?
The question clawed at Zen's mind like a parasite.
The rumble finally began to fade, the storm of power retracting back into Ren's body. Slowly, his shoulders slumped, his breathing ragged. His eyes were distant, haunted, as though he had seen something far beyond what mortals were meant to witness.
The silence that followed was deafening.
"What… was that?" one of the guild members finally dared to ask.
Master Kuro stepped forward, his expression calm, though his sharp eyes betrayed the weight of what had just happened. "It was nothing for you to fear," he said firmly. "Ren was using a weapon—one that demands a tremendous amount of energy. That is why it seemed as though he was unleashing such power."
The gathered crowd glanced nervously at one another before reluctantly accepting the explanation. It was easier to believe that lie than to accept the truth—that a boy of Rank F had just shaken the earth.
Soon the courtyard emptied, leaving only Ren, Yume, and Master Kuro under the pale light of the moon.
"Ren…" Yume stepped closer, her voice gentle but filled with worry. "Why did you suddenly scream for everyone to stop? And what did you mean by 'not killing the child'?"
Ren didn't look at her. His hands trembled slightly as he spoke. "I… saw something. A vision. Children—innocent children—being slaughtered by people who were supposed to protect them. It felt so real, like I was standing right there in the blood-soaked mud."
His words were heavy, carrying the weight of that unseen massacre. Yume's expression softened, but before she could reply, Master Kuro's voice lowered to a whisper.
"You must push the Black Heart to its very limits," he said quietly, almost as if the night itself might be listening.
"…Yeah," Yume murmured after a pause. "You're right."
From the shadows, someone else was listening.
Zen.
His fists were clenched so tightly that his nails bit into his palms.
The Black Heart… that's how he got this power. That's what gave him the strength to stand above everyone else.
His heart twisted.
Why him? Why not me?
And then—
"You… the king…"
A voice boomed inside Zen's skull, deep and cold, like it had been waiting for centuries to be heard.
Zen staggered, his eyes wide.
The King?
An old rumor resurfaced in his mind, the urban legend of the Black Heart choosing a ruler—the King of Shadows.
Ren… is the King?
Something in him snapped. Jealousy ignited into a blazing, ugly obsession.
If he's the King, then I'll take it from him. That heart should be mine. It was always meant to be mine.
Days Later…
The forest was eerily quiet. The sun had barely begun to set, staining the sky in bruised purples and blood-red streaks.
A man stumbled into the courtyard where Master Kuro, Yume, and Ren stood. His clothes were torn, his body slick with blood and mud.
"P-please… help us!" he cried, his voice breaking. "Our team… we were attacked by demons… please, someone!"
Ren didn't hesitate.
Lives are at stake. I can't waste a second.
He sprinted into the forest, his boots pounding against the earth. The wind howled through the trees, carrying with it the stench of blood.
But when he reached the location…
Silence.
The kind of silence that doesn't belong to a forest but to a graveyard.
"Is anyone here?!" Ren shouted, his voice echoing through the empty clearing.
He took one cautious step forward—
click.
A steel jaw clamped shut around his leg.
"What the—?!" Ren cried out as pain shot through him.
Shadows shifted in the trees. Figures emerged from the darkness, their eyes glinting with malice.
Zen stepped forward, smirking.
"Well, well… looks like the chicken fell into the trap."
Ren's face hardened. "What do you want?"
"Nothing," Zen said coldly, drawing a knife, "except the Black Heart you're hiding."
Ren's stomach dropped.
No… he knows.
"What are you talking about?" Ren tried to keep his voice steady, but Zen's smirk only widened.
"I just need to confirm it."
And before Ren could react, Zen lunged.
The blade pierced Ren's chest with a wet, sickening sound.
"AAAHHH!"
Ren's scream tore through the forest, raw and agonizing.
Blood sprayed across Zen's hands as Ren collapsed to his knees, gasping for air, his vision spinning.
Zen's eyes locked on the thing pulsing within Ren's chest—the Black Heart, alive, radiating dark power.
"I was right," Zen whispered, his grin almost feral. "You really are the King. But not anymore."
He dug his hand in and ripped the Black Heart free.
Ren's scream became a choked sob.
"No—Zen… don't…" His voice was barely a whisper.
But Zen pressed the Heart into his own chest.
And the forest exploded with power.
"STOP!"
Master Kuro's voice rang like a gunshot. He and Yume appeared at the edge of the clearing, both battered but ready to fight.
But it was too late.
Zen's body convulsed as the Black Heart fused with him. His veins turned black, shadows swirling around him like living serpents. His grin stretched wide, too wide, as though madness itself had taken root.
"Yes…" he breathed, the sound halfway between laughter and a growl. "This is what I always deserved."
Ren lay in the dirt, barely conscious.
Inside his fading mind, a voice rumbled—the Darkness itself.
"Your friend has stolen what was yours. What will you do?"
"…What can I do?" Ren muttered weakly. "He was the one who gave me a reason to grow… to fight…"
"NO."
The Darkness roared like a beast.
"I chose you. You are my King. Not him. He is a thief. A pretender. YOU are the true King."
Outside, Zen's roar shook the trees as he unleashed his newfound power. The Third and Fourth Generals materialized, their auras blazing, ready to stop him.
But Zen met their combined assault head-on.
The clearing became a battlefield. Explosions of shadow and steel lit the night as Zen grew stronger with every passing second, the Black Heart feeding his hunger.
"This power doesn't belong to a weakling like Ren!" Zen howled, his voice breaking with manic laughter. "It belongs to ME!"
One final strike sent both generals crashing into the ground, barely clinging to life.
Zen turned, his bloodstained eyes settling on Yume.
"And now… I'll kill her. Right in front of you, Ren. Let's see how much of a king you are when everything you love is dead."
Yume stood despite the blood dripping from her lips, her bones aching, her body screaming at her to fall.
Even if it kills me… I'll protect Ren.
Zen's hand shot out and wrapped around her throat, lifting her into the air.
"You die first," he hissed.
"Grandfather!" Yume's voice was hoarse as she reached toward Master Kuro, who lay broken, barely breathing.
"Yume… run…" he begged, blood pooling beneath him.
But before Zen could crush her neck—
"STOP!"
A voice like thunder split the night.
Zen's head snapped around—
Ren stood there.
No longer trembling. No longer weak.
His eyes glowed with black fire.
"The power you stole…" Ren said, his voice low and filled with fury, "was never the true source."
The earth shook.
BOOM.
Shadows erupted outward like a hurricane. The sky turned black as night, blotting out the moon.
Ren's body became shrouded in darkness, his aura monstrous, rising far beyond 90%. The sheer force of it knocked Zen back.
I won't let you hurt them. I won't let you take everything from me.
"Why did you hurt Yume?" Ren's voice was no longer just a voice—it was the roar of a King. "Why did you hurt Master?!"
A scream tore from his throat, shaking the heavens.
And then it appeared.
A colossal phoenix of pure darkness erupted from behind Ren, its wings spanning the sky. Its body burned with black fire, its cry echoing like the end of the world.
Zen's grin faltered.
Ren's glowing eyes locked onto him.
"This ends now!"
The phoenix descended with a deafening roar, its wings blotting out everything, bringing with it the wrath of a true king.