Qiong stood alone in the train's front carriage.
The silence felt unnatural—not peaceful, but earned. Only hours ago, this space had been crawling with reanimated crew members, their hollow groans echoing through the metal corridors. Now, nothing stirred. No movement. No sound beyond the low hum of the train settling into stillness.
Her B-Tier Skill, Protective Light, pulsed faintly around her, thinning her presence until she felt more like a passing thought than a living being. It had allowed her to move unseen, to dismantle the undead efficiently and without confrontation. Each strike had been clean. Each body had fallen without ever knowing she was there.
Too easy.
That realization stopped her cold.
A seductive pull tugged at her awareness—the promise of the final carriage, the dormant locomotive engine, the supplies that had to be there. Her light responded instinctively, flaring brighter, urging her forward.
Qiong forced it down.
Ease bred carelessness. And carelessness killed.
Her father's voice surfaced unbidden, sharp and steady as it had been during their old survival drills.
"Overconfidence is a slow-acting poison, Qiong. You take the first sip thinking you're fine. You never notice it killing you."
She exhaled slowly.
This train wasn't a prize.
It was a trap made of steel.
Charging ahead now—alone, hungry, exhausted—would be suicide disguised as ambition. She had survived this long by refusing to mistake luck for strength.
So she chose restraint.
Not retreat. Preparation.
Fourteen days.
Two full weeks dedicated not to expansion, but to fortification. If this train was going to be her sanctuary, then it would become an unassailable one. She would turn survival into certainty.
Her focus turned inward.
The Core Heart answered immediately.
She began with the carriage itself.
Placing her palms against the cold metal wall, she let her awareness sink deeper. The train responded—not with sound or movement, but with knowledge. Stress fractures. Load limits. Structural weak points revealed themselves as naturally as breathing.
She upgraded deliberately.
Weakened joints thickened. Rusted seams sealed. Thin panels reinforced into dense plating. A shattered control console was repurposed into a solid internal barrier. Flimsy latches hardened into heavy-duty locking mechanisms. The glass windows clouded, then clarified into reinforced plexi that dulled sound and resisted impact.
The outside world faded.
Inside, the carriage became a bunker.
She moved on to tools.
A dull kitchen knife became balanced, keen-edged, dependable. The first-aid kit followed—its contents pitiful at first glance, but ripe with potential. Bandages regained strength and flexibility, the fibers subtly enhanced to encourage faster clotting and mild regeneration. Antiseptics were purified and strengthened, capable of combating infections far deadlier than anything pre-Apocalypse.
Each upgrade demanded energy.
Each success demanded restraint.
Fatigue crept in slowly, testing her discipline. Whenever exhaustion threatened to overwhelm her, her D-Tier Stamina Regeneration pulled her back from the brink, restoring just enough clarity to continue.
Day by day, brick by brick, her fortress took shape.
She learned the rules through repetition.
Large structures—the carriage itself, the locomotive—resisted change. She could only push the engine to the peak of E-Tier efficiency before the drain became dangerous.
Medium objects—locks, doors, partitions—proved more cooperative. Four upgrades in succession before exhaustion forced her to stop.
Small objects were another matter entirely.
A hand-crank radio. Batteries. Even a rusted motorbike secured in the cargo area.
These were malleable.
She could take a small item through every stage—mundane to F, E, D, C, B, A, and finally S-Tier—before fatigue set in. Each transformation taught her more about the Core Heart's rhythm, its thresholds, its generosity.
All of it was cataloged meticulously in her mind.
All except one thing.
A blank space.
A question she had avoided for days now pulsed at the edge of her thoughts.
What happens if I use Core Heart on itself?
The temptation was dangerous. Reckless.
The talent's description was clear: upgrade anything up to S-Tier. But what did anything truly mean? Did it include its own metaphysical structure? Its own governing rules?
If it worked…
What existed beyond S-Tier?
No records mentioned such a thing. Power beyond that rank was theoretical at best, myth at worst.
And if it failed?
She didn't need to imagine the consequences. A corrupted talent. Mental backlash. Permanent damage.
Or worse.
The stillness of the carriage pressed in around her.
Fear surfaced—brief, sharp—but she dismissed it.
Fear preserved life. Knowledge shaped it.
She closed her eyes.
She visualized the Core Heart not as a skill, but as a structure: crystalline, complex, pulsing with ordered power. She did not direct it outward this time.
She turned it inward.
Focused.
Intent sharpened into a single command.
Upgrade.
For a breathless moment, nothing happened.
Then—
A flicker.
The Core Heart stuttered.
Using S-Tier Talent: Core Heart to Upgrade S-Tier Talent: Core Heart…
Calculating Upgrade…
Calculating Upgrade…
Calculating Upgrade… Error!
Her stomach dropped.
Cold surged through her chest as instability rippled outward. The sensation was wrong—disorienting, nauseating, like the floor shifting beneath her feet.
Calculating Error…Calculating Error…
The messages repeated, spiraling into a mental feedback loop. Her head throbbed as pressure mounted, the talent straining against its own limits.
She clenched her teeth.
Stopping now could leave the Core Heart fractured—half-rewritten, unstable.
She held on.
She demanded resolution.
Silence fell.
Not relief—absence.
Then, a decisive chime resonated through her being, deeper than anything before.
Calculating Upgrade…
The errors vanished.
Energy flooded her—not draining, but expansive, as if something fundamental had unlocked.
Upgrade Complete.S-Tier Talent: Core Heart → SS-Tier Talent: Core Heart
The words burned brighter than anything she had seen before.
The change was instantaneous.
Boundaries she had once sensed—rigid, absolute—collapsed into open sky. The limits of possibility stretched outward, vast and undefined. She no longer perceived objects only as they were, but as layered spectrums of potential.
Qiong opened her eyes.
The train hadn't changed.
She had.
The carriage was no longer just shelter. It was raw material. The world itself felt… editable.
A slow, fierce smile curved her lips.
The apocalypse had frozen civilization.
She had just learned how to fast-forward.
What came next wouldn't be restoration.
It would be reinvention.
And it would begin here—on a silent train, with a heart that had learned how to surpass its own limits.