Transmigrating as an Extra, But the Heroine Has Regressed?!

A soft, golden light filtered through his eyelids, but it carried no warmth. He tried to move, to breathe, to open his eyes, but his body felt something very strange.

Thrum.

A low, distant heartbeat echoed in the void.

Kael's eyes snapped open.

He stood on the edge of Arcadia Academy's grand courtyard. But something was wrong. The courtyard was not the one he knew from the first year.

Students moved past him in small groups, their uniforms bearing the crest of a higher rank.

Their faces were both familiar and strange. Taller. More mature. Scarred from training and battles.

"This is… the second year," Kael whispered.

He looked down at himself. His own body had changed, broader shoulders, longer hair tied back, a faint callus along his palms where sword hilt met skin.

He touched his chest and felt the faint thrum of mana coursing through him.

The Ashen Core inside him pulsed stronger than he remembered.

He staggered forward.

The academy buildings stood taller, banners flapping in a restless wind.

Training fields stretched across the distance where new students sparred, their magic flaring in bright colors.

But Kael's heart pounded with a strange certainty: These are memories of the future.

"Am I in the novel?"

Suddenly he was in the second-year arena.

He watched himself—a slightly older Kael—standing across from Edwin in a duel.

Sparks of mana cracked against the stone floor as swords clashed. Sweat dripped from his brow, and a sharp pain burned in his left arm where Edwin's blade had grazed him.

(I remember this), Kael thought.

This was the day he mastered the second form of the Dark Edge sword art. He remembered the outcome: a narrow loss that pushed him to train harder than ever.

The dream version of himself gritted his teeth and lunged forward, dark energy wrapping his blade as he struck.

The crowd erupted with a mix of cheers and gasps.

The image wavered like a reflection in disturbed water.

He now stood beneath the moonlit spires of the academy's tower.

Snow drifted lightly around him, settling against his cloak.

In front of him stood Elysia.

She was older too.

"You can't keep fighting alone," she said with anger.

"The demons are gathering. If you keep pushing yourself like this, you'll—"

Kael—his future self—cut her off with a faint, tired smile.

"I can't stop. If I hesitate, people die."

Elysia reached for his arm, but before she could speak again, the dream shifted violently.

Heat.

The world erupted into chaos.

Flames scorched the sky crimson. Shattered fortresses littered a battlefield drenched in blood and ash.

The smell of burning flesh struck Kael.

He stumbled forward, covering his mouth as screams echoed through the air.

Soldiers in Arcadia's colors clashed against towering demon warriors, their black armor glistening like obsidian.

The ground quaked with every swing of their massive weapons.

Kael's eyes locked onto a figure in the distance—himself again, but older still.

His third-year self.

His armor was battered, streaked with demon blood. His sword—that sword, the impossibly heavy one gleamed with dark energy.

He cut through demons with a precision born from desperation, his movements a blur of rage and exhaustion.

"Hold the line!" his older voice shouted hoarsely.

"Protect the healers!"

Around him, friends and classmates fought fiercely: Edwin unleashing blazing strikes, Cecelia weaving barriers of golden light, Jin swinging his twin sword like a storm.

Elysia stood at the center.

Yet despite their combined strength, the demons were endless. Massive winged fiends swooped down from the blood-red clouds, tearing through battalions with claws of shadow.

Kael's chest tightened as he remembered.

"This is the war… the Demon War of the third year from the novel"

The ground trembled violently, and the sky darkened further.

A towering demon lord emerged from the haze. Its voice rolled across the battlefield like thunder.

"Your world ends tonight."

Kael tightened his grip on the black sword.

"Not while I still stand."

He charged.

The world blurred into streaks of red and black. Kael's heart raced as he watched himself fight with a reckless fury.

The clash shook the very earth, sparks of dark energy slicing through the air.

He felt every swing, every impact, as if the battle lived inside his bones.

But then—another shift. A softer sound cut through the chaos. A faint metallic chime.

The battlefield dissolved into darkness.

Kael now stood in a cavernous hall lit by a ghostly blue glow. Ancient stone pillars rose around him, etched with runes that pulsed like living veins.

At the center of the hall lay a pedestal of black marble. Upon it rested a small, weathered coin—no larger than a silver piece.

The coin gleamed faintly, its surface carved with a pattern of swirling stars.

The Ancient Coin.

He remembered the name like a whisper from a novel. A relic said to predate the founding of Arcadia itself.

In the third-year war, it had been the object of endless rumors—a key to something lost, something beyond the war. A weapon? A portal? None knew for certain.

Even the author hasn't mentioned that.

As Kael reached for it, a voice rippled through the chamber.

"Only one who bears the weight of both worlds may claim the path."

The coin pulsed with a faint golden light. When his fingers brushed its surface, a shock coursed through his veins.

Images exploded in his mind: towering ruins beneath a sky of twin moons, seas of silver sand, a city swallowed by vines of crystal. A single name burned into his thoughts like fire.

The Lost Land.

He staggered back, gasping.

He knew the stories, whispers of a place erased from the novel.

Scholars dismissed it as a myth. Yet the visions were too vivid to deny.

The Lost Land existed.

And the Ancient Coin was the key to unlock all the maps.

"Find it," the mysterious voice whispered, echoing across the chamber.

"Or the war you know will be only the beginning."

Then!

Kael found himself once more on the battlefield. But now he stood apart from the fight, watching his older self clutch the same coin, its glow barely visible against the blood-red sky.

Demons roared in the distance as Arcadia's forces regrouped.

His older self turned suddenly, eyes locking directly onto the dreaming Kael.

For the first time, Kael felt as if the future version of himself saw him.

The older Kael's expression was grim, yet his eyes carried a quiet fire.

Darkness swept in. The battlefield, the academy, the ancient hall—all dissolved into an endless void.

Kael felt himself falling, weightless, the echo of his own heartbeat growing louder.

Thrum.

Thrum.

Thrum.

Then he shouted, "ASTRAL PUNCH", releasing the skill so strong that he could feel the power of it.

He was facing a demon lord.