Chapter 15

In this world, I was a strong man.

I didn’t know why, but this world favored me.

In terms of talent, system mechanics, and magic, I was powerful.

I’d come to understand this over the past few days, using the threat of a duel to make Alken and his group submit.

—To put it simply, I had let it go to my head.

Having obtained power that rivaled veterans of this world in just a few days, I had arrogantly assumed that I had no enemies on these floors.

But I was wrong. A threat—a monster—that could actually end my life was standing right in front of me, talking away.

“I felt some humans hunting Hangshadows at quite a remarkable speed, so I came to take a look. I thought it might be a party of six, but it seems I was mistaken.”

The humanoid mass of black liquid who called himself Teida spoke as he plopped down onto the ground from the ceiling.

At the sheer abnormality of the sight, neither Diablo nor I could find our words.

The alarm bells in my head were screaming.

This guy is dangerous.

The way he spoke unilaterally, a trait of the truly powerful.

The absolute fearlessness.

Dangerous.

“And it turns out the ones left behind are two very interesting children. …What do you say? Care to take my trial? Though humans have reached the 23rd floor, everyone bypasses the 20th ‘Trial’ of the 20th floor. If you defeat me, you’ll become heroes.”

The black mask chuckled as it spoke.

The invitation felt like a devil’s bargain; it made me want to turn tail and run immediately.

However, I remained calm, mentally calculating a way to escape from this demon.

While I did so, Diablo began speaking to Teida in my stead.

“A-are you… that 20th-floor boss that they say no one has ever defeated…?”

“Indeed.”

“The rumors were true about your appearance… It’s a famous story that even the ‘strongest’ explorer, Glen Walker, couldn’t lay a finger on the 10th and 20th ‘Trials’…”

“How nostalgic. Master Glen, was it? I believe we clashed a few years ago. He was on the right track, but he was lacking just a little bit more.”

Diablo seemed to know about this monster, Teida.

Apparently, he was an existence that had become a legend among explorers.

If the situation was that dire, we only had one option.

“—Run! Dia!!”

There was no reason to take risks here.

If he really was the 20th-floor boss, the logical thing to do would be to challenge him after steady leveling, with full MP and in perfect physical condition.

We were still only on the 5th floor.

At the very least, he wasn’t an opponent to fight in a place like this today.

At the same time I shouted, I tried to dash toward the exit of the room, but—

“We’re in the middle of a conversation; I can’t let you leave. Alti, if you please.”

I skidded to a halt as I saw a girl standing in my path.

“—!”

The girl called Alti radiated an aura of abnormality that was every bit the equal of Teida’s.

Taking the form of a petite, red-haired girl, her body was wrapped tightly in bandage-like strips inscribed with characters. And more than anything, her legs weren’t flesh and blood—they were made of pure fire.

Emerald-green flames erupted from beneath the bandages, allowing her to float in mid-air.

“No passage.”

The girl named Alti expressed her intent to block us with a bizarre, crushing pressure.

Instead of trying to force my way through, I pulled up her information.

“…!!”

I was speechless.

If the information was correct, this was the guardian of the 10th floor.

Then why…!

This is only the 5th floor!!

“Christ, we have to do this. I believe we can win against anyone. I believe in us.”

I heard Dia’s voice from behind me.

Realizing we were being pincered, Dia had drawn his sword with a look of grim determination.

—No.

Absolutely not.

Even if Dia was ready, I didn’t want to do this.

This made no sense. If these two really were the 10th and 20th-floor bosses, it was insane for them to be here on the 5th floor.

“Wait, Dia!”

I couldn’t help but shout for him to stop.

Then, I turned back and decided to talk to the monster called Teida.

Yes.

This monster could be reasoned with. If so, there had to be a path other than combat.

“Um… Mr. Teida, would that be alright?”

“Just ‘Teida’ is fine. We are human and monster, after all. Otherwise, it wouldn’t look right.”

“My apologies, Teida. We aren’t looking for a ‘Trial.’ We’d like to leave the Labyrinth right now, actually…”

I politely expressed that I had no intention of fighting Teida.

“Oh? No intention to fight? But, well… We are human and monster. Isn’t it a sort of unwritten law of this world that a battle begins when we meet?”

This bastard—!

His words sounded like an invitation to take a trial, but he clearly had no intention of giving us a choice.

Standing before Teida, who was making his black liquid surge with naked bloodlust, my voice trembled.

“So you intend to fight regardless… No room for discussion.”

I moved closer to Dia while keeping the conversation going.

Either way, I had to coordinate with him.

“The ‘Trials’ of the Labyrinth exist for those who are worthy. You two are worthy. That is what I felt.”

Teida looked like a predator who could hardly wait for his prey.

He praised us, but he seemed eager to be the one to trample us into the dust.

“Christ, let’s just brace ourselves. We’re in the Labyrinth. Things like this happen.”

Dia felt the same.

He was actually smiling in the face of a powerful foe like Teida.

He didn’t even try to hide his battle spirit, as if he were certain he would be the one to take down this legendary enemy.

Dia’s recklessness was surfacing in the worst possible way.

“Oh, the lovely one over there understands quite well. Yes, excellent. You two are truly excellent. Your talent is one thing, but more than anything, I like your expressions. You look very much like those heroes of old.”

“They certainly do…”

Teida rejoiced at Dia’s fighting spirit, while Alti whispered softly from behind.

“Well then, shall we?”

With that, Teida delivered his final ultimatum.

I immediately clung to Dia’s back, taking a defensive stance against Alti behind us.

Seeing this, Teida continued as if remembering something.

“Ah, two-on-two isn’t really what we’re looking for. A Labyrinth boss has to be fought alone.”

Teida spoke with the lightness of someone discussing fashion, casually offering to halve his own advantage. Seeing him attempt to adhere to some sort of internal rule, I racked my brain for a breakthrough.

“Which of us should go first, Alti? If we’re going in order, you—the one in charge of Floors 1 through 10—should be first.”

“No, I’ll pass. I still have things to do in this world… I’m so close to resolving that doubt…”

“I see. Then I shall do it. Alti, just seal the room for me. If you would, block it off with those flames.”

“Understood.”

While I watched the flow of the conversation with trepidation, the two monsters cheerfully hammered out the logistics.

If there were an opening to flee, I’d take it, but one didn’t seem easy to find.

Still, listening to them, it sounded like a two-on-two clusterfuck could be avoided if we just waited.

Alti erupted in flames, creating walls of black fire at the room’s entrance and exit.

“We’re on a ‘Mana Line,’ so I can’t hold this for long. See you, Teida.”

“Yes, thank you.”

With that, Alti vanished into the flames.

The nauseating pressure of being sandwiched between bosses eased slightly.

However, her parting gift had robbed us of our retreat.

“Now, the field is prepared. From this moment on, this—this very spot—is the 20th floor. The stratum of Teida, ‘The One Who Steals the Dark Principle.’ My apologies for the makeshift nature of this away-mission, but please consider this flame-shrouded space the 20th floor. Now, you shall undergo the ‘Twentieth Trial’!”

Teida’s mask grinned.

He was serious now.

The mana swirling around Teida pulsed, making the very air twitch.

The last traces of Teida’s humanity were stripped away as his body metamorphosed.

His arms became massive blades.

His legs turned into the curved limbs of a beast.

“Magic: 《Dimension · Gladiator》!”

I chanted the spell.

Coinciding with its activation, the black liquid that maintained Teida’s humanoid shape twisted and—leaped.

In the blink of an eye, Teida was upon Diablo. I perceived his bladed hand swinging downward.

“Diablo!”

I shoved him out of the way, shielding him from Teida’s lethal blade.

“—! So, you can see it!”

Teida shouted with delight while cold sweat poured down my face.

I could see his movements. But my body couldn’t keep up.

The fact that I could barely react even with magic sent a shiver of terror through me.

《Dimension》 was the foundation of my strength.

If this failed me, I’d have nothing left.

The word “Escape” flashed through my mind.

I immediately discarded it. Since the enemy was faster, it wasn’t realistic—and there was no way that wall of black fire was just normal flames. Running was impossible.

“Take this—!!”

Clinging to a sliver of hope, I swung my one-handed sword at Teida’s black torso.

However, the only response was the ring of metal on metal.

My horizontal slash was blocked by Teida’s hardened, transformed hands.

Then, Teida moved.

He swept his hands along the flat of my blade.

The target of that sweep was my grip.

To avoid losing my fingers, I let go of the sword.

For a fraction of a second, the blade hung in mid-air.

I immediately snatched it back out of the sky and lunged straight for Teida’s face.

It was an exchange that lasted only an instant.

A supreme feat of skill achieved through 《Dimension》.

But Teida saw it clearly and parried the thrust.

And then, he laughed.

“Ha… Hahaha! That skill, that speed—you’re top-class for a human! Yes, you truly are worthy!!”

“《Flame Arrow》!”

A flash of light pierced Teida’s black torso.

It was a spell from Dia, who had been chanting even as I shoved him aside.

A hole opened in the black torso, and Teida stiffened.

“Eat this!!”

Not missing the opening, I closed in and delivered a diagonal slash.

“We did it!”

Dia cried out in joy as our coordination landed a full hit.

We had opened a hole in his chest and sliced his body in two.

He looked certain of our victory.

But I grimaced and put distance between myself and the enemy.

The unnatural amount of cold sweat hadn’t stopped since the fight began.

“—Ha… Haha. It’ll take more than that to end this. After all, I’m a monster.”

Teida’s mask twisted into a smirk.

The hole in his torso sealed shut, and the blades on his arms shifted again.

His hands fused together, transforming into a massive hammer that came crashing toward me with immense force.

“—Ghah!!”

I excelled at dodging linear or point-based attacks by a hair’s breadth, but I was weak against wide-area “surface” attacks.

Caught off guard by the sudden change in weaponry, the edge of the hammer’s face clipped my body.

Even though it was just a graze, the incredible impact lifted me off my feet and sent me flying.

I was thrown several meters, tumbling across the Labyrinth floor.

A dull pain—one I hadn’t felt in a long time—shot through my body.

Then, it hit me.

Since I’d started using 《Dimension》, this was the first time I’d actually taken damage.

A crack formed in my absolute trust in my magic.

“But truly, impressive. The lovely one’s magic took quite a chunk out of me. And the nimble one’s slash was excellent. I believe I died twice just now.”

Teida dissolved the hammers, swinging his whip-like arms around as he spoke playfully.

Checking my injuries, I pondered his traits.

—Yeah, he’s got the traits of a textbook game boss.

Does he have a separate main body? A core weak point? Are only specific attacks effective? Or, based on his tone, do I just have to kill him over and over? Take your pick.

This is ridiculous.

I’d understand if this were a boss in a game designed to be beaten. But this isn’t a game.

Can I really trust that there’s a “way to win” just like in a game?

There’s always the possibility that it’s already checkmate and there’s no way to win at all.

“You seem to be pondering how to kill me. I’d love to tell you, really, but then it wouldn’t be a ‘Trial’ for you, would it? It’s a secret.”

Damn it…

He’s an expert at getting under my skin.

If you want to tell me, then tell me—!

“Christ, what should we do!?”

“Just keep doing what you’re doing! If you see an opening, blast him with everything you’ve got!!”

I gave Diablo his orders and lunged forward with everything I had.

Ultimately, I lacked too much information.

All I could do right now was—

“Magic: 《Dimension · Gladiator》!!”

Carve this smirking face in front of me into pieces!

“Even faster!?”

Teida met my desperate charge with admiration.

Honestly, in a normal fight, my sword wouldn’t work.

More importantly, my MP was running dangerously low.

Whatever happened, this had to be a short-term decisive battle.

To achieve that, I had no choice but to gamble.

I closed the distance to zero in an instant, dropping my center of gravity.

Then, I drew the sword held in my right hand from my left hip in a lightning-fast strike. That was all, but I poured every ounce of strength and speed into it. It was a single flash at full velocity, disregarding mana consumption and physical stamina.

Teida tracked the flash with his eyes, attempting to strike it down with his right blade.

The enemy’s movements were fast enough to make that possible.

Thanks to 《Dimension · Gladiator》, I perceived that world in units of less than a tenth of a second. I grasped the movement of space down to the millimeter.

Time compressed.

It felt as if the mana coursing through my body and the adrenaline in my brain were undergoing a chemical reaction.

Within that vivid—yet slow—flow of time, I piled deliberation upon deliberation.

I calculated the optimal move to seize control of this split-second exchange—

First, I used my gauntleted left hand—the one not holding the sword—to strike the side of Teida’s blade as it tried to parry my flash.

The technique, which allowed for not a millimeter of error, succeeded, causing Teida’s downward swing to veer slightly off-course.

Next, maintaining my momentum, I twisted my body to the absolute limit of human flexibility. I succeeded in fully evading Teida’s bladed arms without letting them graze me.

—The result.

Only my flash remained, bisecting Teida’s abdomen.

“Not yet—!”

Even so, I didn’t let down my guard or my assault.

I swung my sword upward to shred Teida’s face.

In response, even as he was being cut in two, Teida tried to swing his blades again. My heightened senses allowed me to dodge them one after another by a hair’s breadth. And then, I kept cutting Teida’s head—from above, from the side, diagonally—over and over and over. Again and again and again—

“Take thiiiiiiiiiiiiiiiiiiiiiiis—!!”

I slashed and slashed and slashed.

Teida’s body was hacked into pieces, the fragments falling to the floor.

Finally, the black gel-like substance lay scattered on the ground, motionless.

“Haah… haah… haah—!”

I did it.

If this wasn’t “defeating him,” then what was?

But I had a premonition.

The layer of ice covering the edge of my heart wouldn’t melt.

One of the black gel fragments wriggled, forming a mouth, and spoke.

“—Kuh… kaha… hahaha… I can’t keep up… I lose in both speed and skill. In that case, let’s counter with magic… with Magic.”

“DIABLOO!! FIREEEE—!!”

I screamed in terror.

“Leave nothing but ash!!《Flame Arrow》!!”

In response to my scream, Dia unleashed a spell packed with an unprecedented amount of power.

That 《Flame Arrow》 wasn’t the usual type that pierced in an instant.

It had a wider area and a longer duration; it was almost a different spell entirely.

The overwhelming heat began to incinerate Teida’s body parts scattered on the ground.

However, it wasn’t enough to leave “nothing but ash” as promised.

Some fragments remained; they wriggled and gathered in one spot. Then, Teida’s chant was completed.

“He… hehe. Magic: 《Variable Curse (Washing the Dark Heart)》.”

The moment he finished the chant, a black curtain fell over my vision.