The moment Eren stepped out of the golden hall, a sharp wave of dizziness struck him like a hammer. His knees almost buckled, and he gritted his teeth as his vision blurred for a split second.
The Grimoir of Infinite Malice pulsed beside him, its pages shimmering with newly formed runes. The recent trial had drained him more than he realized—not just physically but mentally.
"I passed the test, but at what cost?"
His mind was still reeling from the fight against his own reflection. The darkness within him—the part of himself he had been ignoring, suppressing, fearing—had been exposed in its rawest form.
And he knew now.
It wasn't gone.
It was still lurking beneath the surface, waiting for a moment of weakness.
He shook off the exhaustion and pushed forward. The golden hall behind him faded into the void, replaced by something new.
A massive staircase stretched before him, descending into an abyss of swirling darkness.
A single, towering obsidian door stood at the bottom.
And he knew.
This was the final threshold.
---
The Whispering Abyss
As Eren stepped down the staircase, the air grew colder. Heavy. Suffocating.
The whispers returned, but this time they weren't just voices.
They were memories.
His father's disappointment.
The scorn of his peers.
The agony of his first failure.
The guilt of the lives he couldn't save.
Each step made them louder.
"Weak."
"Worthless."
"You will never be enough."
Eren's jaw clenched as his hands curled into fists.
"No."
He forced his mind to focus.
These were illusions—shadows trying to tear him down.
His Grimoir pulsed, responding to his defiance, and the whispers began to distort. The shadows around him twisted, writhing like dying creatures, as if his resolve had burned through their lies.
Finally, he reached the obsidian door.
And as soon as he touched it, everything collapsed into silence.
---
The Forbidden Chamber
The door swung open, revealing a vast chamber lined with towering statues—each one depicting ancient figures clad in dark robes, their faces hidden beneath hoods.
At the center of the room stood an altar, upon which rested a black crystal pulsing with an unnatural glow.
The moment Eren laid eyes on it, his Grimoir reacted violently.
Pages flipped on their own, revealing new spells, sigils that had been locked away until now.
"This is it. The final piece."
But before he could take another step, the statues moved.
One by one, they turned their heads, their empty eyes locking onto him.
Then, they spoke in unison.
"Are you willing to pay the price?"
The chamber trembled, and the weight of something ancient and immense pressed down on him.
Eren exhaled slowly.
"There's always a price for power." His eyes burned with determination.
"I'm ready."
---
The Trial of Souls
The black crystal erupted with a surge of energy, and in an instant, Eren was somewhere else.
A battlefield.
A hundred corpses littered the ground.
And standing among them—
Was himself.
But this wasn't like before. This wasn't a mere reflection.
This was a future.
A version of himself that had taken every shortcut, every dark path to power.
The Eren before him was clad in black armor, his eyes devoid of emotion, his presence crushing, suffocating.
A Grimoir floated behind him, but it was no longer just a book. It was a mass of living shadows, tendrils of pure malice curling around him like a second skin.
This was the Eren who had lost himself to the Grimoir completely.
And he was smiling.
---
Clash of Fates
"I expected more resistance," the other Eren said, his voice a chilling monotone. "But I suppose deep down, you already know."
"Know what?" Eren asked, his hand tightening around his weapon.
"That this path only leads to one end." The dark Eren gestured to the corpses. "You will walk over the dead. You will become a monster. And in the end…"
His eyes gleamed with an eerie crimson glow.
"You will have no one left."
Eren's heart pounded.
Because a small part of him knew.
This wasn't a lie.
If he let the Grimoir consume him completely—if he let his hunger for strength override everything else—then he would end up alone, feared, hated.
But…
If he didn't take this power…
If he hesitated…
Then he would never be strong enough to protect what mattered.
"So what do I do?"
The dark Eren smirked, raising his hand.
"Let me show you what happens when you hesitate."
Black flames erupted from his palm, surging toward Eren like a tidal wave of destruction.
Eren reacted instantly, his own Grimoir flaring to life.
"Abyssal Barrier!"
A dome of dark energy surged around him, absorbing the impact, but the sheer force of the attack sent cracks splintering through the ground.
"He's stronger than me."
Eren gritted his teeth, feeling his mana drain at an alarming rate just from blocking the attack.
His doppelgänger vanished, reappearing behind him in an instant, a black dagger aimed straight at his spine.
Eren twisted his body at the last second, but—
SHLK!
Pain exploded through his side.
Blood dripped down his cloak.
The dark Eren leaned in, whispering in his ear.
"You're still too slow."
Eren gritted his teeth.
He wouldn't lose.
Not to himself.
His Grimoir flared, and for the first time, Eren stopped hesitating.
He let the power flow freely.
The air crackled.
A new spell unlocked itself.
"Shadow Dominion!"
Darkness erupted from his body, swallowing everything in an endless void—
And when the shadows cleared, only one Eren remained standing.
---
The Price of Power
Eren staggered forward, his breath ragged.
The black crystal had shattered. The chamber was silent.
But his Grimoir was different now.
The runes had changed.
The power was his.
But so was the burden.
He had taken another step forward.
But now, there was no turning back.
---
Author's Note
Hey everyone!
Sorry for the late upload—I wanted to make sure this chapter had the intensity and depth it deserved!
Eren's choice was crucial. Does power always come at the cost of humanity? He's walking a fine line, and I'm curious—what do you think?
Drop your thoughts below, and I'll see you in Chapter 70!
— bloodyking99