Lynx had poured over the research journal extensively.

And in doing so, he came to understand exactly why this entire mess was happening—and why it was currently driving him mad.

"This is… absolutely insane."

Lynx let out a curse in sheer disbelief.

He had been cursing more than usual lately, but frankly, he had no choice. Even a saint would lose their composure after reading this.

First things first.

The nameless mage's research focused on two major subjects.

[Phase 1: Using artifacts with my own mana]

[Phase 2: Studying the purity of mana]

The two were organically intertwined, and both had reached a certain level of completion.

Especially the first.

In order to use an artifact, the mana from the magic stone must not collide with the mage's own mana—right?

But studying that required a large supply of magic stones. Gathering that many would inevitably reveal that the mage was conducting secret research.

So the owner of the lab had used slimes instead.

The slime's nucleus, in all its simplicity, bore certain similarities to a magic stone.

It had no intellect, no will, and barely any instincts beyond survival and reproduction—making it ideal.

The first phase of the research was a success.

The mage had then moved immediately to the second.

Imbuing the slime's core with his own pure mana, he sought a way to enhance its purity.

The first step had been to measure purity itself.

Understanding how pure mana was quantified meant understanding the mechanism by which it could be improved.

And so the slimes became the subjects of relentless experimentation.

What became of them?

They all died.

All except the one that had survived—and was still there.

So you're telling me… that slime's mana is purer than mine…?

Should he be shocked? Devastated?

Lynx couldn't manage his expression.

He'd studied magic for thirty years before his regression.

He'd even absorbed artifacts said to be made by the Empyreans.

And now… his mana was inferior to that of a slime, the kind you'd find in any random cave in the hills?

"Unbelievable."

It was maddening—but according to the journal, nearly certain.

That's why magic didn't work on it.

Normally, one mage's magic wouldn't mix with another's.

If the same spell was cast at the same time, the two would clash and cancel each other out—they wouldn't amplify or merge.

The academic community believed this was because a mage's unique traits were embedded into their magic.

After all, didn't each mage have their own mental landscape?

They had assumed that was the reason.

But no.

According to this research—

It was because the mana's purity was the same, so they collided.

And through continued experiments, the slime's mana had become far purer than Lynx's.

Which meant that like a stream flowing into a river, and the river into the sea… by the laws of nature,

Lynx's mana was being absorbed by the slime.

Magic might still activate and cause damage,

but the mana infused within was simply being siphoned away.

Naturally, the magic's power dropped dramatically.

And the slime used that mana to grow.

That was likely a trait unique to the slime species, with their gelatinous bodies.

Any other monster might have experienced a different transformation instead of size increase.

"The more I think about it, the more disgusting this is."

Lynx murmured, feeling a shiver creep up his spine.

He'd thought it was just coincidence—a test subject that had somehow survived and ended up blocking the lab entrance.

Slimes could live for a whole year on just one small rat.

So what about this one?

Its mana had been artificially purified through experiments. It would survive much, much longer.

But isn't it too convenient to be just coincidence?

If someone entered the lab not with a key, but by deciphering the magic circle, they were certainly a high-circle mage.

And what would that mage do upon seeing the slime?

They'd probably fire a spell at it without hesitation.

After all, a three-meter-tall slime was far too large for soldiers or knights to simply slice up with swords.

That spell would be absorbed—and the slime would grow.

The mage would panic and cast more spells.

It would grow again.

Eventually a knight would step in, radiating aura and swinging their sword.

But—

Aura is mana too.

The slime would absorb that as well—becoming colossal.

Then what? Strengthen your body with mana and try slashing it?

Like Zeron's sword… everything would just melt in its acid.

Swing without mana? The blade melts.

Encase it in mana to protect it? It gets absorbed—and the slime grows again.

An endless, maddening cycle.

Eventually, you'd have no choice but to punch it barehanded.

A slime with extreme acidity—faced with unprotected fists, devoid of mana…

This is insane… whether you're a knight or a mage, the moment you make a single wrong move, you're dead. If you'd just used the key and entered normally, the slime probably wouldn't have appeared at all.

Which explained why the mercenaries before Lynx's regression had left with the mana formula unscathed.

Now, he understood the purpose of the experiments.

He knew the slime's ability, and that it had become a trap.

Only one problem remained.

So… how do I survive this?

The slime, having absorbed all that mana, had grown to a monstrous size.

There was no path around it—he had to attack.

But Lynx's magic would be absorbed.

He had no weapon.

What was left?

Nothing but death.

Forty years—across two lifetimes before and after regression.

Within all the knowledge Lynx had accumulated, there was no way out.

Except for one.

Thud.

Closing the journal, Lynx stood and shouted.

"Zeron!"

"Yes, Mage!"

Came the response from down the hall.

"How far has the slime come?"

"About halfway through, Mage!"

"The pace—is it accelerating?"

"No, sir! It's not speeding up, but it's already gotten pretty close! Are we in danger now, maybe?"

"Just hold on a little longer! I think I've found a way!"

"Ha! Got it, Mage!"

Once he confirmed the slime's position, Lynx closed his eyes and focused his mind.

As always, he headed into the mental world—

the place shaped by his inner self.

A black sea. [Dark Ocean]

Step.

Lynx now stood before the slime.

It was still advancing from far down the corridor.

Somehow, it had grown even larger.

Lynx already knew why.

The ambient mana had thinned around him—he could feel it on his skin.

Astonishingly, the creature had begun absorbing even the natural mana in its surroundings.

"…"

He quietly observed it.

Its appearance had changed significantly.

Still round in shape—but lighter in color.

Where it had once been a translucent grey, it was now completely see-through, revealing the wall behind it.

That meant only one thing—its mana had become even purer.

"Horrifying."

Across its front were clusters of small, rough nodules.

Ten tentacles—longer than before—writhed through the air, probing blindly.

A revolting sight by any standard.

Had Zeron seen this, he might've fainted from the shock.

Fortunately, Zeron wouldn't be seeing any of it.

"Snore… snore…"

He was asleep in the corner, thanks to Lynx's sleep spell.

He had to be put out, forcibly—because what was about to happen wasn't something Zeron could be allowed to witness.

Step.

Lynx took a step toward the slime.

The tentacles began to contract.

A clear pre-attack signal.

The distance between them was around fifteen meters.

The last attack's range had been five—so they still had room.

And yet, it was already reacting.

Which meant only one thing: its attack range had increased.

And it clearly had no intention of hiding that.

Lynx knew slimes weren't supposed to be intelligent.

But the way it moved now—it radiated something almost like malice.

Could this, too, be the result of its mana growing purer?

"..."

Regardless, Lynx said nothing.

He merely prepared to do what he had to do.

That was:

To cast a spell that would burn the slime to ash.

"Here we go."

With that quiet mutter, like a vow to himself, it began.

Slowly, black smoke began to rise from Lynx's body.

Hssssss.

Have you ever stood under the summer sun in the middle of a scorched field?

The wavering heat haze that blurs the horizon, makes your head spin and your thoughts grow strange—

That's what it resembled.

Black vapor shimmered and twisted around Lynx like that strange mirage.

Then—

Shhhhhh...

The haze became an aura.

Ssshhhhaaaaaaa—

And that aura bloomed into dark currents, expanding outward in all directions.

Darkness engulfed the entire space.

"..."

Lynx raised his hand, examining it carefully.

The fog of darkness had swarmed around it, cloaking his fingers in mist.

Even faced with such a bizarre sight, Lynx wasn't alarmed.

Because that darkness was his own mana.

To be exact—

He had drastically reduced the density of his mana, then exhaled it like vapor into the air.

And this wasn't just ordinary mana.

[Corrupted Mana]

The kind required to cast black magic.

So then, how had Lynx gained the ability to use the mana of dark mages?

"Come."

The word emerged in a low, eerie voice—like the wail of some formless beast or a specter howling in the void.

At that single command, the darkness trembled.

From deep within the sealed blackness, Lynx's faint silhouette shimmered like a ghost.

A spark.

His eyes, stained crimson by corrupted mana, gleamed sharply.

That was the signal.

All the surrounding darkness surged toward him—

gathering, condensing in front of him with a sound like grinding static.

Zzzzzzz—

The friction was unnatural, uncanny.

Mana compressed into a tight sphere, round and dense, about the size of an apple.

But it was so potent, so destructive, that the space around it appeared to warp and distort.

And then—

From Lynx's lips came a small word, pitifully simple compared to the terrifying mana it commanded.

"Dark Fire."

The spell activated.

Fwhoomp.

At first, it was just a black flame.

No bigger than a fingertip.

It appeared suddenly—right inside the massive slime's body.

The creature rippled, its gelatinous form quivering as if laughing—mocking the spell's tiny scale.

[...!?]

But that was the arrogance of a single-celled creature.

The black flame blooming inside the slime didn't go out.

Far from it—it grew.

From the size of a candle flame, to a lantern.

Then to the size of a grown man's torso.

Soon, the dark fire began to spread throughout the entire massive body of the slime.

[Gggguuoooorrrrrhh....]

For the first time, the slime made a sound.

The agonized moan of a voiceless, mucous mass—

A desperate will to live, awful in its alien intensity.

But it was too late.

Splorch, splorch.

With every sluggish movement it made, its body dripped—melted away.

The black sludge that oozed from it looked like thick tar.

And still, it didn't die easily.

A great, flaming bulk, it staggered down the corridor, burning.

It wandered and writhed and sloshed forward—

Until finally—

Ssssshhhhh...

It collapsed into a wide pool of muck on the floor.

And vanished.

Black magic!

That was the first thing Lynx had thought of after reading through the entire research journal.

Black magic.

Among mages, it was believed that a dark mage's mana was artificially "corrupted."

Whether it was truly corrupted or not, one thing was certain:

It was fundamentally different from ordinary mana.

More destructive.

More violent.

And—

The only thing that leaves a deep scar on purity… is corrupted purity itself.

If the slime's mana was extremely pure, then corrupted mana—black magic—was its perfect counter.

On top of that—

Luckily, I can actually use black magic.

Thanks to the metal plate attached under Lynx's robe.

That plate allowed him to wield black magic.

Well, not pure black magic, strictly speaking—but modified magic imbued with curses.

Even so, it was more than close enough.

Take Fireball, for instance.

With a curse, it changed.

Where a normal fireball exploded with heat and flame—

A cursed fireball clung to its target, burning with sticky black fire that refused to die.

Ideal against slimes.

But there was one problem.

The slime's just gotten way too big.

Lynx couldn't cast cursed spells infinitely.

He could only use the curses stored in that metal plate.

And judging by the amount of curse it held, he could fire off maybe three, four fireballs.

Would that be enough to burn such a massive thing completely?

Would it be enough to pollute all that pure mana?

No. No matter how I calculate it, it's not enough.

It would definitely do some damage—but not enough to annihilate it.

He had considered weakening it just enough to flee, but discarded the idea.

Too many unknowns.

If he failed, he'd lose his life—simple as that.

So there was only one option.

To use even more black magic—stronger, larger.

Lynx had found the clue in the journal.

The key lay in the mental world.

El—Astaroth created stars in his mind.

Seasons.

Nature itself.

Nature cycles.

Cycles create mana.

Not external mana, but a mage's own unique mana.

That, said the journal, was how mana becomes pure.

Strengthen your mental world, and your mana becomes purer.

Which raised a new question—

What if the mental world is stained with curses? Does mana become murky?

And so Lynx made a decision.

He gathered all the curses stored in the metal plate…

and poured them straight into his mental world.

I can't believe I actually did something this idiotic…!

Have you ever seen a drop of black ink fall onto a sheet of white paper?

A lump of mud thrown into clear water?

That was what happened to Lynx's mindscape.

In an instant, it was contaminated.

And in that moment, Lynx realized something.

He would never again be able to use normal magic.

Not until all of this corrupted mana was purged.

Damn it.

But what could he do?

In life, to gain one thing, you often have to give up another.

So Lynx gave up his mana—

And extended his life.

In any case, his gamble had succeeded magnificently.

The black magic, dripping with endless malice—

The corrupted mana—

Thoroughly tainted even the slime's purest essence.

Ssshhhlluuuurp.

And so the slime lost its form, completely…