The Mysterious Child: An Adventure Tale Beginning with Numerology

The Stoania Kingdom is a state that prioritizes reasoning arts.

You hardly see any magical devices here. There are only reasoning devices that even I can use. The toilet flush is a tank system, and the water supply uses faucets. The stove burns gaseous fuel, and room lighting is oil-based.

After living here for 4 years, I have only one impression.

This country is... the best!

In the Muuteru household where I lived during my childhood, there were only magical devices. Everything was magical devices, magical devices, magical devices!

Because of that, I had to carry a water bucket to the toilet, and we lived without even turning on lights. Having been used to such a lifestyle, this country is truly easy to live in.

The city is lively with various races.

There's an abundance of ingredients, making cooking worthwhile.

The water and sewage systems are well-developed, clean, and orderly.

Streetcars run through the city, making transportation easy. It costs money, but since the earnings are good, it's not a problem at all.

"I'm going to settle down here in the future."

"Mm, me too."

Elen seems to like it too.

The whole country prohibits racial discrimination, and everyone at the Adventurers' Guild is nice. Of course, there's the Guild Master, the 【Cheap Beer】 trio we've become friends with, Iso-san the barmaid, and all the other adventurers are fun people. It's such a comfortable life that we don't need to leave here—

"Oh, right. After we defeat the 100th floor boss, we're going on another journey right away. Specifically, today."

"Huh?"

I freeze at Roze's casual words.

Our master's schedule changes are always sudden, but this is too abrupt.

Leaving this comfortable city... y-you're joking, right?

"W-why?"

"There's a rumor about an interesting child. I thought I'd go see if I want to make them my disciple."

A new disciple!?

This is completely out of the blue.

After being with this unreasonable master for 4 years, my abilities have improved considerably.

My adventurer rank is the city's average of B, but I've long surpassed the average level, so I could call myself a full-fledged adventurer. That's why I can say this. I can look the new disciple straight in the eye and say:

Don't do it with this master.

Of course, it's different if they have qualities like Elen or some special talent.

Really, I don't know how many times I've nearly died.

Actually, just yesterday, we had intense training where Elen and I had to keep challenging the 98th floor boss separately until we could defeat it. I, who hate effort, even stayed up all night.

Thanks to that, we managed to conquer it, so today we're challenging the memorable 100th floor. I wonder what kind of monster we'll face. Rumors say it's an S-rank monster. S-rank is like Fenrir class, right? Thinking about it, it seems pretty strong.

Well, more importantly.

"There's going to be a new disciple, Elen. What kind of person would you like?"

"Mm, good cook."

"Right?"

Elenora, the unwavering woman.

Wouldn't it be better to just hire a cook?

Both of us earn quite a lot in the dungeon, so our pockets are pretty warm. We could even say we have enough savings to be called wealthy. People like us are apparently called dungeon tycoons.

"Mm, no strangers."

"You're shy, aren't you?"

"Can't make pudding either."

"Well, that can't be helped."

It's not a dessert from this world, after all.

As we chatted idly like this, we arrived at the dungeon entrance.

The dungeon is set up so that you can teleport every 10 floors, and your progress can be recorded on your adventurer card. As usual, we check in at the reception and enter the room with the teleportation device, selecting our current progress point—the 100th floor.

"Oh, right, Elen. Think about what you want for dinner tonight, we'll celebrate conquering the 100th floor."

"Mm. Vegetables and meat."

"What kind of meat?"

"Steak."

"Okay. Let's splurge on something expensive."

"...I shouldn't be the one to say this, but you two really have no sense of tension, do you?"

While we were talking like this, the teleportation completed.

The space that opened up when we exited the teleportation room was an empty void.

It's incredibly spacious.

The ceiling is probably about 100 meters high. It's too far to tell how far the walls are. The ground is just soil, but it's warm. There are no visible distinguishing features.

The 100th floor is a good milestone, and this clear view probably means it's a room for just the boss battle with no small fry. This dungeon had such rooms every 10 floors, so this one probably has the same structure.

Of course, from here on, there's no advice from Roze. We have to conquer it completely on our own.

While I stand a bit ahead observing the surroundings, Elen begins a long incantation.

"—I command, deliver the prayer of the wrathful apostle from the sky, O one who commands pure magic, illuminate the life of the stars with thy refined work, and find the light of the woven soul—"

Even for a magical prodigy, this spell still requires an incantation.

That's because this is an extreme-level magic called forbidden magic.

Forbidden magic refers to formulas that the "Central Magic Academy" has prohibited from being passed on to others. Currently, there are 11 types of formulas registered in the forbidden magic catalog.

The general effects of forbidden magic are posted at the Adventurers' Guild for anyone to check for free. All 11 types have extraordinary effects, but only eccentric researchers would try to imitate and develop such formulas.

Except for us.

"—Though there is nothing that can be seen through with that pure soul, there is nothing that cannot be seen through. Only those darker than twilight do not answer my song's call. Though the voice returning from their marrow is unseen, my eyes receive a clear revelation—"

Elen originally had innate talent. And we have an immortal master who's like a walking encyclopedia. Add to that my modern knowledge from Earth, and what do you think happens?

The answer is simple.

We were able to imitate forbidden magic.

"—None escape from my arms, their guidance brings about a reunion, and fate returns to the innocent. Ancient magic, all to my wisdom—'Full Scan'"

The effect is simple. It's an omnidirectional, all-purpose enemy search within the effective range.

It uses only lightning attribute and pure, attributeless magical power.

If you pursue the lightning attribute to its limits, you arrive at electromagnetic force. If you can manipulate electromagnetic force, you can create electromagnetic waves. If you spread those electromagnetic waves and pure magical power like "sonar detection" and understand the physical structure of the surroundings from their reactions—when I jokingly proposed such a theory, Elen actually created it.

As expected of Elen. I'm thrilled and admire that.

It's a magic that absolutely cannot be created without being well-versed in both reasoning arts and magic, but thanks to that effort, no existence can escape Elen's eyes within the formula's range.

No matter where they might be hiding, even if they're invisible.

Elen suddenly shifted her gaze to the ground.

"Mm! Below!"

"'Relative Transfer'!"

I grab Elen and teleport us to a distant point in the air.

Immediately after, the place where we were standing is engulfed as if melting into a giant mouth. The desert monster Sand Worm makes a similar attack, doesn't it?

What swallowed the earth from underground wasn't a worm, but a pitch-black, slime-like substance.

It slithers out onto the ground.

The mouth that should have eaten the ground is nowhere to be seen, and now it's just a viscous, massive body writhing about. Not only can we not tell where its face is, it's doubtful if it even has a fixed shape.

Hmm. Given its existence as a large mass of mud-like substance with that huge body, there's only one monster it could be. I dig up the memory from the monster encyclopedia I've read.

The 'Mud Viscous King' Shoggoth.

Of course, its monster rank is S, boss-class.

[TL notes: Shoggoth images from google :D]

Its movements aren't particularly fast, but don't underestimate it as just a mud monster. This one has the characteristic of nullifying physical attacks and the ability to recreate the physical features of all the prey it has eaten so far, making it a versatile weapon. It even has regenerative abilities.

To defeat it, you'd have to either repeatedly attack with magic faster than it can regenerate, or throw it into a magma pool larger than its body. Of course, there's nothing like that here, so our only option is to attack.

For ordinary adventurers, it would be an opponent they wouldn't know how to defeat. At S-rank, it's an enemy that would require mobilizing several units of a country's knight order to subdue, and it's rarely seen outside of dungeons. As expected of the 100th floor boss.

But well, it was lucky for me.

If it's a famous monster that appears in encyclopedias, I've had plenty of time to think about strategies to defeat it. Plus, over these 4 years, we've undergone Spartan training in preparation for all kinds of opponents. It was really tough, I tell you.

I teleport to a place away from the Shoggoth and say,

"Elen, buy me some time."

"Mm."

Elen nods.

Now then, speaking of Shoggoths, it's from the Cthulhu Mythos, right?

Shoggoths appear in many stories, but what they all have in common is their "immortal regenerative ability". Because of this, they're terrifying opponents that eventually grow to a size that can swallow stars. There was even a theory that they became the origin of Earth.

It would have been good if there was a legend about destroying them, but as far as I remember, Shoggoths always ended the stories without dying. That means, unfortunately, I can't create a conceptual weapon using "Legend Manifestation".

But well, the Shoggoth in this world probably isn't such an overwhelming opponent. It's just a monster after all.

Simply put, if we kill it, it dies.

"'Ice Blizzard'"

Oh, nice!

It seems she chose a composite magic of ice and wind, anticipating that the opponent contains a lot of water.

The Shoggoth's body hardened and became almost immobile.

It was quite easy to stop its movements, but this is thanks to Elen's magic having an abnormally wide range and power. Normally, it wouldn't cover an area large enough to envelop the Shoggoth's body, nor would it freeze it solid.

My partner has done her part well. I can't fail on my end.

I mutter this quietly and start kneading spiritual essence.

"Phew."

I concentrate.

Mystic arts are equations using spiritual elements. Precise calculation power is crucial. The initial deployment formula borrows the basics of the substitution method. The range is a familiar fist size. Environmental information is incorporated into it, equipping it with spiritual elements. Secondary information is not included, leaving it as a mass of air. After setting the coordinates for substitution, the transfer preparation is confirmed and fixed in a pending state.

Next, the pending formula itself is transcribed. The set number is 2 to the 18th power—262,144 in total, confirmed by "Threshold Compilation". Execute—transcription complete.

Then, the array information is also set by "Threshold Compilation", immediately executed—array changed. Reconstruction into a cube completed.

What's been created before my eyes is a huge cubic mass of air reinforced with information.

Calculationally, it's properly one size larger than the Shoggoth.

All that's left is to teleport this.

I aim with my fingertip and mutter,

"'Great Rupture Bullet'"

The inspiration for this technique came from something Roze said long ago: "Even if the body after teleportation is embedded in an object, because the existence intensity of our side, reinforced with spiritual essence, is stronger, the thing at the destination breaks while we're unharmed." The slight wind that occurs when teleporting to an empty space is proof of this; the air that was originally there bursts and creates a different air current.

So, I wondered if we could weaponize this difference in existence intensity.

That's how I came up with and refined this original coordinate attack formula—"Rupture Bullet".

If the opponent were a Cthulhu Mythos level Shoggoth, even this might not work, but what's in front of us is just a big viscous king with tremendous regenerative and mimicry abilities.

Therefore—

ZUPAAAAN!

The Shoggoth that was at the destination where the mass of air teleported shattered into pieces.

Ice crystals dance in the air like sand.

Surely it can't regenerate from this.

"Wow... I really feel sorry for any living creature you use that technique on. Make sure you never use it on a person."

"I understand. Only against monsters."

After confirming that the Shoggoth had vanished, Roze patted my shoulder, saying "Good job."

"Besides, Elenora's magic had already nearly killed it."

"Is that so? As expected of Elen."

"Mphh~"

The same relaxed atmosphere as always.

Just then, the reward chest for clearing the 100th floor dropped where the Shoggoth had been.