A dark, damp forest stretched endlessly beneath a shroud of mist, alive with creatures both magical and grotesque. Strange forms moved between twisted trees, their silhouettes flickering in the gloom like restless spirits. Deep within this forest lay a swamp, perpetually cloaked in a corrosive, toxic fog that ate away at anything foolish enough to linger too long.
At the very heart of this swamp stood a seven-story stone tower.
Or rather, it existed—though no ordinary creature could perceive it. The entire structure was concealed beneath a powerful invisibility spell, rendering it unseen by both magical beasts and human eyes alike. It was a silent fortress, hidden from the world.
At the tower's peak, within a dimly lit arcane laboratory, Linn stood still, staring at the corpse of a grotesque, two-headed serpent sprawled across the floor. Its massive body twitched faintly as residual magic dissipated from its scales.
He exhaled slowly, tension leaving his shoulders.
A translucent blue screen appeared in his mind at a mere thought:
[Current Level: 10 → 11]
[Unlocked Spell Slot: 6th Circle (1/1)]
"Level 11… finally… finally level 11."
His voice trembled slightly. Emotion welled up in his chest, and for a brief moment, his vision blurred.
It had taken him over a year.
One full year of relentless hunting—slaughtering every viable creature in this cursed forest—just to push that final one percent of experience and break through from level ten.
Linn was not originally from this world.
Ten years ago, he had been an ordinary person, sitting in front of a computer, playing Baldur's Gate 4 late into the night. At some point, exhaustion overtook him. He blacked out—and when he awoke, everything had changed.
He had awakened in the body of a dead man.
A poor soul who had died from a snake bite in this very forest.
That should have been the end of him. Instead, it was the beginning.
Because along with his transmigration came something extraordinary—a "golden finger."
The blue interface in his mind: his D&D Character Sheet.
Though he inherited the body, he gained none of its memories. He didn't know where he was, what this world was, or who the original owner had been.
Fortunately, the body itself had some advantages.
It appeared the original owner had been a mage, possessing decent base attributes in Intelligence and Perception. Combined with the system's guidance, Linn successfully chose the Mage class and began his new life.
At first, survival was his only concern.
He hunted small creatures, cautiously exploring his surroundings, all while searching for a way out of the forest.
That plan changed the moment he encountered it.
A strange entity drifting silently through the trees.
At a glance, it resembled a wraith—but his system identified it as something far more dangerous: a Demilich. Yet, beyond that name, all information was unavailable. Even its Challenge Rating was obscured.
Curious, Linn cast a few basic cantrips at it.
To his utter shock, the creature died instantly.
And just like that, his level jumped to two.
That wasn't all.
Not long after, he encountered the same creature again.
And again, it died just as easily—granting him more experience.
With his gaming instincts kicking in, Linn quickly realized what he had found: a respawning monster.
A renewable resource.
For a beginner like him, it was nothing short of a miracle.
Though the experience gained diminished as he leveled up, it never became insignificant. Instead, it scaled proportionally—granting percentage-based progress.
And so, for nine years, Linn did the same thing.
He farmed.
Relentlessly.
Day after day, year after year, he hunted that creature, growing stronger at a steady pace.
Until one day… it vanished.
No warning. No trace.
Just gone.
Without it, Linn lost his primary source of experience. Progress slowed to a crawl. For an entire year, he remained stuck at ninety-nine percent of level ten.
Until today.
"It's a shame that thing disappeared…" he muttered, glancing at the serpent's corpse. "But at least I finally broke through."
A faint smile appeared on his face as he felt the surge of magic coursing through his body.
With a thought, he opened his spellbook interface.
"At level eleven… I can finally learn Disintegration and Globe of Invulnerability."
His eyes gleamed with anticipation.
"With these as trump cards… even a dragon wouldn't be unbeatable."
Then—
A sharp, piercing alarm shattered the silence.
Linn froze.
That sound came from the defensive spells he had placed around the tower. It would only trigger if an intruder breached the outer perimeter.
Ordinary creatures couldn't even get close. The outermost Dispel Magic barrier was enough to repel them.
So this meant only one thing.
Either a high-level magical creature capable of ignoring his defenses…
Or a human spellcaster strong enough to dismantle them.
The first possibility was unlikely. Over the past year, Linn had systematically hunted down every powerful creature in the surrounding area.
Which left only the second.
A human.
And not just any human—a mage.
Without hesitation, Linn waved his hand. A shimmering pool of water formed in midair, its surface rippling as it displayed a distant image.
The edge of the mist.
Space itself seemed to twist unnaturally.
With a soft popping sound—a clear sign of spatial compression—a figure appeared.
An old man.
He was tall and thin, with a long silver beard that nearly reached his waist. Half-moon glasses perched on his crooked nose, and he wore a deep purple robe adorned with stars.
In his hand, he held a small wooden wand.
The system immediately analyzed the target:
[Target: Human Male (Spellcaster)]
[Estimated Level: 15+]
Linn's breath hitched.
"Level… fifteen or higher?"
A chill ran down his spine.
In his understanding, that level represented overwhelming power—enough to destroy cities and cast terrifying high-circle spells.
"Stay calm… stay calm…"
He clenched his fists, forcing himself to think.
He had prepared countless defensive measures. Maybe—just maybe—they would be enough to deter the intruder.
The old man seemed to be searching for something. His expression was thoughtful, almost puzzled.
But it didn't take long.
"A magical barrier…" the old man murmured softly.
His gaze locked directly onto the invisible tower.
Then, he raised his wand.
"Forgive my intrusion. I must confirm whether darkness resides here."
With a simple flick—
The invisibility spell collapsed.
The tower was revealed.
Linn's heart pounded.
"No incantation…?"
"Silent casting…?"
"Activate defense!"
A massive Wall of Fire erupted, encircling the tower in a blazing inferno.
But what happened next made Linn's pupils shrink.
The old man calmly traced a circle in the air.
The raging flames twisted—shrinking, reshaping—until they transformed into a flock of flaming birds.
They chirped cheerfully before flying off into the sky.
Linn stared in disbelief.
"What… was that?"
He didn't even recognize the spell.
Still, he acted quickly.
"Conjure Earth Elementals!"
Three towering stone giants burst from the ground and charged forward.
The old man simply pointed his wand.
In an instant, the giants collapsed into fine white sand.
Two stone lion statues appeared where they once stood.
Linn's hands trembled.
"Instant casting… resistance ignored… permanent transmutation…"
This was beyond him.
Completely beyond him.
The old man walked forward, reaching the base of the tower.
There, he encountered Linn's final defense.
An invisible Wall of Force.
He paused briefly… then flicked his wand again.
The barrier vanished.
Silence fell.
Inside the tower, Linn stood frozen, layers of protective magic shimmering around him. At his feet, a teleportation array glowed faintly, ready to activate at a moment's notice.
"I can't win," he whispered.
"Not even close."
Then—
Knock. Knock. Knock.
Linn blinked.
The old man… was knocking?
A calm, gentle voice echoed directly into his mind:
"My deepest apologies for disturbing your seclusion, unknown sir."
"I am Albus Dumbledore."
"The current headmaster of Hogwarts School of Witchcraft and Wizardry."
"I came here in pursuit of an old friend who has gone astray. Unfortunately, he appears to be absent."
A brief pause.
"May I have the honor of speaking with the master of this place?"
Silence.
Absolute silence.
Linn stood in the center of his teleportation array, unmoving.
His mind struggled to process what he had just heard.
"…What did you say?"
His voice came out hoarse.
"Hogwarts…? Dumbledore?"
A long pause.
Then—
"You're telling me…"
His expression twisted in disbelief.
"I've been grinding D&D mage levels for ten years…"
"And this is actually the world from that children's book series?"