The journey northwest began just as the sun was about to set, painting the sky in shades of orange and crimson. Behind them, the temple that had served as a resting place was now left under the watch of guardian spirits. Ahead, the jagged silhouette of mountains loomed, hiding secrets of the past and the threat of future ruin.
Itsuki, Reina, Hana, Akito, and Miru moved swiftly. The path to Kozame Fortress was not only rocky but also filled with spiritual distortions—traces of chaos left behind by the nearly opened Fifth Gate.
"Kozame Fortress used to be a gathering place for the Heirs," Reina explained as they walked. "But when the Black Emperor fell, it grew silent and was sealed off from the physical world."
"And now that sealed gate is starting to open," Hana added. "Which means something or someone has broken through from inside."
Akito, at the rear, suddenly stopped. "Wait! do you hear that?"
They all fell silent. From beyond the trees came a whispering many voices speaking in a language unknown. Thick fog began to creep in, and the air turned drastically colder.
Itsuki scanned the surroundings. "We're not alone."
From within the fog, dark figures emerged. They were neither spirits nor humans. Their faces were blank, with only hollow holes where their eyes and mouths should be. Their bodies moved unnaturally, like puppets without strings.
"Summoner's Shadows..." Reina murmured. "They've been sent to slow us down."
Battle erupted. Reina and Akito sprang into action, slicing down the creatures with deadly precision. Hana stood beside Yurina, preparing a barrier. Despite the exhaustion from the previous clash, Itsuki summoned the energy within him this time more carefully, so as not to unseal the power hidden in his blood.
With a surge of energy that shook the ground, he unleashed a wave of magic, obliterating the first line of enemies.
But one creature remained. This one was different dressed like an old monk, wielding a staff made of bone, with eyes glowing blood-red.
"You're too late, Heir," it whispered, its voice echoing from all directions. "The Fifth Gate has opened. And the Mark of the Shadow has been planted."
Itsuki stepped forward. "Who are you?"
"I am only a messenger. But look closely at who now bears the mark."
Suddenly, Miru collapsed to her knees, clutching her head.
"M-Miru?" Hana rushed to her, but Miru's body was flung back by an unseen force.
Itsuki looked at his friend and saw a dark symbol slowly appearing on her neck a reversed eye radiating with a spectral aura.
"No. it can't be," Itsuki muttered.
The messenger laughed. "We don't choose the strongest bodies. We choose the hearts most easily fractured. And she bears a wound you've yet to see."
Miru looked up, her eyes now clouded, no longer her own. Yet she was still conscious fighting.
"R-Run... Itsuki… I can't hold it back!"
Itsuki stood between Miru and the messenger. "I won't abandon my friend!"
Akito stepped forward grimly. "The Shadow Mark is a cursed seal. If it isn't cleansed before the full moon, Miru will become the vessel of the oldest spirit the Void Sovereign."
Reina drew her sword. "We need to reach Kozame and find the Sanctum of Purification before time runs out."
Itsuki knelt beside the semi-conscious Miru. "I promise, I will save you. You won't be alone."
As the fog slowly lifted, only they remained in the forest shaken, wounded, but still standing.
Kozame Fortress now stood visible in the distance. Towering in the shadow of the rising moon. The Fifth Gate had opened. The Mark of the Shadow had appeared. And their time was running out.
---
—Voices from the Fifth Gate
Kozame Fortress finally loomed before them. Its walls stood tall, covered in moss, parts of it crumbling with age. An ancient aura surrounded the place once a training ground for the heirs of ancestral power. Now, it served as the final line of defense between the human world and total annihilation.
Their steps were cautious and slow. Miru, still carrying the Shadow Mark, was protected by Hana's energy barrier, keeping her soul intact. Though not fully conscious, she occasionally whimpered, as if battling something within.
"This place is full of whispers," Reina murmured, gazing at the ruins of the entrance gate. "It's like the old spirits never left."
"Kozame isn't just a fortress," Akito replied quietly. "Beneath it lies the Blood Purification Altar. But to access it, we have to relight the Four Pillars of Light. Without them, Kozame's guardian spirit will attack anyone who enters."
They moved through narrow, dark corridors. The walls were etched with ancient symbols, some of which glowed faintly as Itsuki touched them. The energy in his blood reacted, as though the fortress recognized him.
"The first pillar," Akito said, pointing to an open chamber with a five meter tall statue. In its hands was a large, unlit torch.
"I'll light this one," Reina stepped forward. "The Pillars of Light require a sacrifice of life aura."
She bit her thumb and let her blood drip onto the base of the torch. Blue light ignited instantly, shooting into the ceiling and flowing toward the eastern corridor.
Three pillars remained. As they headed to the second, a rumble echoed from below. The ground shook. Walls groaned.
"Something's awakening," Hana whispered.
Suddenly, a lion-like creature with horns and wings burst from the lower chamber, eyes glowing red and fangs bared.
"Kozame's Guardian!" Akito shouted. "It thinks we're intruders!"
Itsuki leapt forward. But this time, instead of fighting, he spoke. "I am not your enemy! I am heir to the Black Emperor's blood! We're here to purify the mark of darkness!"
The creature paused, gazing at him. Then it nodded.
A deep voice echoed from within: "Then prove you can bear the weight of that blood."
Suddenly, the entire room transformed. They were transported into an illusion a battlefield from the past. Corpses littered the ground. The sky bled. And at the center stood a man in black robes the Black Emperor himself.
Itsuki froze. The figure looked almost exactly like him. But his eyes were cold, filled with destruction.
"This is my ancestor's memory?" he whispered.
The Emperor stared at him. "You carry my legacy, but do you carry my intent?"
Itsuki shook his head. "I want to protect, not destroy the world!"
"Then prove it!" the Emperor's voice thundered, and the illusion shattered, returning them to the real chamber.
The guardian nodded again and allowed passage to the second pillar.
Itsuki himself lit the second torch. The pillar accepted his blood, and now, two blue beams of light shot skyward from within Kozame, forming a radiant pattern above.
But time was slipping away. Miru began trembling. The reversed-eye symbol on her neck now pulsed, spreading to her chest.
"We have to hurry," Hana urged. "If it reaches her heart, nothing will stop the ancient spirit from entering."
They raced to the third and fourth pillars. Through teamwork and sacrifice, all four were lit. The gate to the underground altar opened dark and shrouded in thick violet mist.
And as they prepared to descend, a voice called from within, "I've been waiting, child of cursed blood."
Itsuki looked downward. There, the true power of the Black Emperor's legacy awaited him. And with it, the voice from the Fifth Gate the entity ready to rise.
---
—The Altar of Purification and the Ancestor's Trial
The corridor leading to the altar felt tighter and more suffocating than they expected. Dense violet fog obscured their vision, turning each step into a gamble. Faint whispers echoed from the walls like prayers repeated in an indecipherable tongue. They weren't alone. The place itself seemed alive, watching them.
Akito lit a flame in his palm, casting light down the corridor. "Keep your minds steady. This mist will prey on your deepest fears."
Suddenly Reina stopped. Her eyes widened.
"Reina?" Hana called, worried.
Reina began to tremble. "I… I see my brother's face. He should've died when the Second Gate opened. But he's here. He's calling to me."
Itsuki looked her in the eye and placed a hand on her shoulder. "That's not him. It's only a reflection of the past. Don't believe what you see."
Reina was silent. Slowly, her eyes refocused. She nodded. "Sorry. I almost lost myself."
They continued forward until they reached a vast chamber half a dome-shaped cavern with a natural ceiling. At its center was a pool of thick black blood, surrounded by glowing runes. Across from it stood a cloaked figure, back turned to them.
"So you've finally arrived," the voice was deep, with a spectral resonance. "The purification can't be delayed."
Itsuki stood tall. "Who are you?"
The figure turned. His face was aged, but his eyes glowed violet the same as the Shadow followers, only deeper, more ancient.
"I am the First Shadow. Guardian of this altar and guide of your legacy, child of the Black Emperor."
Akito drew his weapon. "He's dangerous."
But the figure raised a hand, and Akito froze, unable to move.
"If I wanted you dead, it would've happened long ago. But purification requires the heir's will. I cannot force it. I can only test it."
"Then test me," Itsuki said firmly. "I'm here to save Miru and stop the Shadow's power before the Fifth Gate fully opens."
The First Shadow smiled. "Then step into your ancestor's blood. Face the one who first brought darkness into the world. Only by defeating him can you purify the mark and save your friend."
Without hesitation, Itsuki stepped into the pool of black blood. As his foot touched the liquid, the world collapsed. He fell into a void, then landed on cracked stone.
Before him stood a young man his mirror image, but darker and more powerful. He wore a black-and-gold robe and held a sword made of pure shadow.
"I am Enrai, your ancestor. First Heir of the Black Emperor's blood. I opened the First Gate a thousand years ago."
Itsuki clenched his fists. "Then I'll be the one to close the Fifth."
Enrai smirked. "But do you truly know who you are? Our blood is not a curse it is a throne. You may reject it, but the world will still come for you."
Itsuki stood his ground. "Then I'll face it with my own choice."
The battle began. Shadow and light clashed. Enrai used mind manipulation and illusions, showing Itsuki his greatest fears Reina's death, Hana's betrayal, the world's end. But Itsuki endured, for one reason: his belief in the bonds he had built.
With a final cry, he channeled all his energy and drove pure light into Enrai's shadowy heart. A burst of light consumed everything. When Itsuki opened his eyes, he was back at the altar. The pool was now clear. And Miru slowly opened hers.
"Itsuki… you…" she whispered.
"Welcome back," Itsuki replied with a tired smile.
The First Shadow nodded from a distance. "You passed. But remember, the Fifth Gate is not fully closed. You've only delayed it."
Akito took a deep breath. "We need to move to the next point. Yurina must already be on the move."
And with that, they left the altar stronger, but more aware that the end was drawing near.