The sound of two sets of footsteps echoed softly through the damp stone corridor steady, deliberate.
Riku and Kaela pressed deeper into the ruins, passing chambers whose walls were lined with ancient murals, cracked crystals, and the shattered remains of statues with faces no one could name.
The air here… felt different. Cold, but not from temperature.
It was the kind of cold that seeped from old memories and unhealed pain.
Riku slowed his pace, then stopped.
His gaze fell upon one particular wall.
An ancient relief… depicting a masked man standing between two worlds: one adorned with castles in the sky, the other shrouded in shadow and crawling with monsters.
Beneath it was an inscription in an archaic language but somehow, Riku could read it.
"The Author of Fate shall be born from the Void, to cleave the Old World and the New."
"This… isn't just art," Riku murmured. "It's a warning."
Kaela turned toward him. "You can read that?"
"Somehow, yes." He nodded. "Ever since I got the Rewrite Protocol, I've been able to understand strange symbols."
Kaela bit her lip, tension shadowing her expression. "Riku… I know this place too."
He blinked. "What do you mean?"
She lowered her gaze. "A long time ago, my mother… was hunted by humans because of her mixed blood. She hid me in a place like this. I remember this mural. This… is where she died."
Silence closed in around them.
Riku looked at her face, lined with the scars of old wounds. Something hot and bitter welled up inside him—not only for what had been done to Kaela, but for this world itself… a world that cast aside anyone deemed weak, tainted, or unworthy.
He clenched his fists. "This world is rotten."
Kaela's eyes locked onto his. "Then why are you so calm? After everything they've done to you…"
He was quiet for a moment.
Then, in a low voice, he said, "Because I won't repay them with rage. I'll repay them with results. If this world wants me to die as 'trash'… then I'll become the strongest, and make them regret it."
Kaela studied him in silence… then, for the first time, allowed a faint smile to cross her lips.
◆◇◆
Before long, they arrived in a vast hall. At its center rose a spiral stone pillar, bridging the upper floor to a bottomless chasm.
But something was wrong.
The pillar was encircled by a massive magic formation.
Riku approached cautiously and activated Observe. But when the skill took effect, the results startled him.
[Magic Formation: World-Lock Fragment]
[Origin: Ancient Dimensional System]
[Function: Seals entities from other worlds. Directly linked to the world's core.]
"Sealing… entities from another world?" he murmured.
"Like us?" Kaela asked softly.
He nodded.
Then, suddenly, a mechanical voice echoed from the ceiling.
[Divergent identity detected. Intervention Protocol engaged.]
[Guardian Unit: Sentinel V0-K awakening.]
The far wall trembled.
From behind the stone, a towering humanoid emerged three meters tall, its frame forged of pitch-black metal, eyes glowing crimson. Two mechanical wings jutted from its back, and in its hand crackled a plasma spear, hissing with lethal energy.
Sentinel V0-K. The Last Guardian of the Old World.
"Get ready, Kaela. This… isn't just another monster."
◆◇◆
The battle began.
The Sentinel moved with speed that defied its size. Every motion was precise, and each swing of its spear unleashed shockwaves that shattered the stone floor.
Kaela dove to the left, loosing two arrows in quick succession only for them to bounce harmlessly off its armor.
"Its defenses are too strong!" she shouted.
Riku was already analyzing.
[Observe Active]
[Target: Sentinel V0-K]
– Regenerative armor system
– Power source: Dimensional core
– Weakness: Cannot adapt to non-system manual techniques
"It's immune to regular skills," Riku called out, "but it can be hurt by manual physical attacks if the technique doesn't come from the system!"
Drawing a deep breath, he turned to Kaela. "I'll open a gap. You shoot straight for its core."
"The chest?" she confirmed.
He nodded.
Riku activated the Rewrite Protocol, merging the Acid Body skill with the Energy Manipulation trait he had just logged from the Sentinel's data.
[Combined Skill: Acid Overload Blade]
– A physical weapon capable of piercing magic armor
– Additional effect: Burns the target's internal structure
A jagged blade of violet-green energy flared to life in his hand, unstable and pulsing like it might explode at any moment.
He charged the Sentinel, leapt high, and slashed at its right arm.
Craaaack!!
The arm shattered but the Sentinel twisted in retaliation, slamming a kick into Riku's ribs and sending him crashing to the floor.
"Ugh!!"
Blood spilled from his mouth. But before the Sentinel could close in, Kaela released a single arrow its shaft glowing silver, infused with the blood of both demon and human.
The arrow struck the Sentinel's chest, piercing the core, which split with a jagged crack.
[Critical Hit! Core damaged. Guardian system failure.]
[Sentinel V0-K: Destroyed]
The massive machine collapsed, its remains scattering across the stone. A small shard of crystal tumbled free, landing at Riku's feet.
[Item Acquired: Old World Code (Fragment 1/7)]
[Function: Grants access to Sealed World Layers]
[Additional Info: Activation will reveal Traces of Forgotten Fate]
Riku sat down, breathing heavily.
Kaela, also panting, glanced at him. "That technique you used… it felt like something from this world's humans, but not from the system."
"Yeah…" he replied. "Because now, I'm not just this world's hero… I'm its author."
And from far below the chasm, a blue light began to rise marking the beginning of a new path.