The descent was unlike any before.
Where the Sky Bastion had shimmered with fractured logic and light, the Hollow Vault felt… quiet. Not the stillness of an abandoned ruin, but the heavy silence of something holding its breath.
The stairs of shifting light gave way to a tunnel of obsidian plates, each etched with pulsing glyphs that rearranged themselves when glanced at directly. Yuki took the lead, Kai at his side, Selene trailing a few steps behind with her blade drawn. The air thickened with every step they took downward—charged, as if even the silence had density.
There was no indication of how deep they had gone. No measure of time. Only the sound of footsteps and the occasional crackle of glitch-energy trailing from Yuki's gauntlet.
Finally, the passage opened.
The Hollow Vault revealed itself as a massive underground amphitheater—a spiraling chamber lined with what looked like library alcoves, but each one held no books. Instead, translucent memory crystals floated in mid-air, suspended above metallic caskets labeled in a forgotten language.
Memory Caskets.
Hundreds of them.
Each one humming with contained echoes.
Yuki stepped forward cautiously, eyes scanning the nearest alcove. One of the crystals shimmered, reacting to his presence. He reached out—and the moment his fingers brushed its surface, a rush of voices poured into his mind.
"Subject Z-Kron 01: Failure. Subject Z-Kron 02: Failure. Subject Z-Kron 03…"
A flash of the last prototype. The one he'd seen in ruins. His breath caught.
"Subject Z-Kron 04: Memory Sync Incomplete. Quantum Core Unstable. Disposition: Unknown. Potential: Maximum."
Selene stood beside him now, reading his expression. "You were meant to be one of them."
He nodded. "But I wasn't finished."
A low hum rippled through the vault. One of the caskets opened with a hiss of pressurized air. Inside was a form—skeletal, mechanical, and wrapped in decayed armor. But its core still glowed faintly. Another prototype?
Yuki stepped forward again, but Kai's growl stopped him.
Too late.
The core flared.
Data shimmered through the air, congealing into a form above the corpse. A projection? No—a guardian.
[Warning: Echo Guardian Online] [Designation: Code Archive Warden | Instability: 61%]
The figure was humanoid but wrong. Its limbs bent the wrong way, its face a blank pane of shifting glyphs. Its voice was a distorted echo.
"Unauthorized access detected. Prototype Z-Kron 04… not validated."
It raised one elongated arm, forming a blade of glitch-fire from its wrist. The Vault trembled as ancient runes lit up along the walls. Defense mechanisms activated.
"Here we go!" Selene shouted, already moving.
The Warden moved like light. One second it was distant, the next it was in front of Kai, slashing downward. The glitch-beast deflected with a snarl, his passive activating to absorb part of the impact. Yuki blinked sideways with Phase Drift, appearing behind the entity and striking with Glitch Pulse.
It staggered—but did not fall.
Yuki triggered Shadow Step, teleporting above it midair and dropping down with the force of the Fragmented Gauntlet. The Warden caught the blow with one arm—only for Selene's blade to slice through its knee joint from below.
[Warden Instability increased: 61% → 67%]
"Yuki!" she called. "Its data field is resisting complete sync. We need to break the anchor glyphs!"
Yuki activated Echo Sight. The vault rippled, and the glyphs revealed themselves—three anchors at the far edges of the amphitheater.
"I'll go left," he said. "Kai, right. Selene, center!"
They scattered.
The Warden howled—a shrill, echoing wail that triggered a shiver in Yuki's spine. The floor shifted, platforms rising to block his path. But he leapt across, momentum carrying him through, slipping between rifts in space created by his Phase Drift.
The anchor glyph shone bright red. With one strike, he drove his gauntlet into it—and felt the resistance collapse.
One down.
Kai slammed his body into the right glyph with a burst of glitch-light, sending it sparking into collapse.
Two.
Selene danced across falling debris, slicing through summoned echoes—half-formed memories of dead prototypes—as she reached the final glyph. Her blade pierced it clean.
Three.
The Warden's form buckled. Its blade arm dissolved. It screamed—
Yuki was already moving.
He leapt from a floating platform, activating Glitch Pulse in both hands this time. Midair, he spun, merging the pulses into a vortex.
Skill Fusion Possible… "Quantum Flare Pulse" Created.
The strike landed dead center in the Warden's chest.
A blast of energy lit the Vault like a supernova. The Warden shattered—its data shell fragmenting into a thousand glowing shards, which disintegrated before they hit the ground.
Silence.
Then, the vault began to shift again. The caskets receded. New paths revealed themselves.
From the shattered remains of the Warden, a data shard floated up, pulsing with incomplete protocols.
Yuki grabbed it.
Memory Fragment Recovered: "Chrono Lock Project"
Selene exhaled, wiping her blade. "Another secret."
Kai barked softly, sniffing at the now inert floor.
Yuki turned to face the Vault's heart—an enormous gate, dormant but humming with energy.
"It's not the end," he said. "The Hollow Vault… It's not hollow. It's sealed."
Selene stepped beside him. "Then what lies deeper?"
He clenched the shard in his hand. The unknown skill inside him flickered, resonating again.
Processing Chrono Data… Sync Incomplete… Awaiting Core Trigger…
The journey was far from over.
But somewhere ahead, past the locked gates, buried in ancient systems and broken dreams—
Was the truth of what Yuki was meant to become.
And why he was never meant to survive.