Chapter 168 - Traveler III

"..."

The air was cold.

Daggers flew into my chest.

That was no mere metaphor. Most of the Undertakers here had attained the realm of the Mind Sword. Formless blades crossed back and forth along their gazes.

Of course, no one here was the sort to die from a few slashes. Undertakers that weak had already become bowling balls, rolling down the plane's aisle.

These were masters against whom victory in a “discussion of swords” was by no means assured!

Having reconfirmed that none of their peers were pushovers, the Undertakers finally laid hands on their sword hilts.

"We can no longer verify who's real through the Saintess."

"Unfortunate."

"It's about to get even more unfortunate. Sorry, but I don't have the confidence to live in a world with fifty-one Go Yoris."

"No. Fifty-one Commander Noh Dohas frighten me more. Understand? If each one chokes you just once, you're strangled to death on the spot."

"Fifty-one Sim Aryeons would be no joke, either. SG Net would perish that very day."

Tension filled the air. The regressors exchanged fierce stares and engaged in a battle of nerves.

It was a hair-trigger standoff: the instant anyone drew a sword, a fight to the death would begin.

"Everyone, stay your blades."

At that moment, I—the original Undertaker, more legitimate, upright, and exemplary than anyone else—spoke up.

The other false Counterfeitakers turned toward me in unison. Among them were a Mustached Counterfeitaker and a Female Counterfeitaker.

"What? Want us to kill you first?"

"No. On further reflection, killing one another isn't our best option."

"Why?"

"Getting cold feet?"

"You know perfectly well that provoking me like that won't accomplish much. Anyway, this is practically a meticulously constructed trap. If we launch into a slaughter now, a great calamity will befall us later."

Several Undertakers tilted their heads.

"A great calamity?"

"Yes. Let me ask you this first. Do you all know about the 'gu-poison jar'?"

Gu poison.

A very famous spell. Think of it as an ancient game of Pokémon.

First, a spellcaster carefully selects venomous insects and fills a jar with them. Then they close the lid and announce the start of a PUBG tournament.

The tournament continues until only one insect remains alive.

The final champion, which has hunted down and devoured every other pest. A legendary-tier venomous insect.

"Is there anyone here who doesn't know that?"

"Hear me out. What happens if we slaughter one another? Naturally, only the most powerful Undertaker will survive."

I spoke with every eye on me.

"From that moment on, we'll have defined this plane ourselves as a 'gu-poison jar.'"

"...!"

"The attributes of 'insect' and 'venomous insect' will naturally attach themselves to the final survivor. In other words, you might wake up one morning to find you've become a bug."

Groans escaped from all over the plane.

"That certainly makes sense."

"Good grief. We're caught between a rock and a hard place!"

"If the plane lands like this, the anomalies will double in number. But if we start killing one another, we'll bring about the tragedy of defining ourselves as insects. What are we to do?"

"Wait."

The Female Undertaker shot up a hand.

Her long hair was tied back, and she looked like a cocktail of equal parts Dang Seorin, Noh Doha, and the Saintess. She was also the only—no, one of only two Undertakers here, including me—dressed as a barista.

For the record, she'd chopped off about twenty other Undertakers' heads all by herself.

Her combat strength was probably comparable to mine. She warranted close attention in more ways than one.

"I understand the reasoning that killing one another would turn this into a gu-poison jar. But is acquiring an insect attribute really that dangerous?"

"A foolish question. You don't know the dangers of insects? Surely your worldline has had a Giant Potato-Robot-Saintess Statue erected in Busan?"

"Huh? Giant potato... what?"

Ah, so she didn't know.

I looked around with a pitying gaze. Everywhere I looked, there were nothing but half-baked Undertakers.

"I'll explain, so listen carefully. As for what a potato-robot-Saintess is—"

A FEW MOMENTS LATER...

A little later...

"Bullshit!!"

"Good God. That actually happened?"

"My Saintess would never!"

Pandemonium broke out aboard the plane.

Of course, it was hell only for the Undertakers. The Dang Seorins wore expressions that said, “Saintess? Who's that?” and “Who dared erect such a blasphemous statue in Busan, my turf?”

Ignorance was bliss.

"Anyway, insects are dangerous. This anomaly has laid an elaborate scheme and trap aboard this plane. In all likelihood, an Ocean-class anomaly is lurking behind it—perhaps even a God of Alienation-class one."

"Ah... ah."

"I understand how dangerous insects are, at least..."

Yes. If you didn't want to wake up one morning as “Gregor,” you'd better steer clear of insect attributes.

"Then what should we do?"

The Undertakeress spoke, having barely recovered her composure.

"No. 107. If, as you say, we're fucked if we land like this and fucked if we kill one another... isn't it already over?"

I shook my head.

"No. There is one way."

"What way?"

"Gu poison only works as a spell because the insects trapped in the jar slaughter one another."

I infused my voice with power so everyone could understand.

"Therefore, if the insects don't fight one another, yet only a single insect remains, the anomaly's spell will not take effect. Its very premise will have collapsed."

"...?"

"Ah."

Several Undertakers blinked. I had to wonder how those birdbrains had managed to function as regressors.

On the other hand, some versions of “me” were fairly quick on the uptake.

The Undertakeress belonged to the latter group.

"We just have to kill ourselves. Until only one person remains."

"What?"

Dang Seorin, who had been listening quietly beside me, started in shock.

"Kill yourselves? All of you?"

"Yes. That's the solution your Undertaker has proposed. A way to select a single survivor without killing one another."

"Aha!"

"An ingenious move!"

"A good strategy. That will let us avoid both 'Go Yori times fifty-one' and the 'gu-poison jar.'"

"No... that's utter nonsense."

Dang Seorin—and all the other Dang Seorins—looked incredulous.

The Undertakers, however, exchanged covert glances with me. They all looked convinced.

Though we'd each followed a different path through life, looked different, and even possessed different levels of intelligence—any “Undertaker” was bound to keep one possibility in mind at all times.

The possibility that someday, we ourselves might turn into anomalies.

The worst possible route.

If we entered that route, an “Undertaker” was prepared to willingly extinguish their own life—and beyond that, their very existence.

"Now we determine who among us is the most capable Undertaker. Through strength, intellect, stories, or whatever else. And whoever loses..."

"Acknowledges their shortcomings and exits, passing the position of Undertaker to the victor?"

"Exactly."

"Fair enough."

The Undertakers spoke.

"But there's one thing."

"A problem."

"I don't mind leaving things to another Undertaker and exiting. A new run will be waiting after I die, anyway."

"But what about Dang Seorin?"

The Undertakers each turned their gaze toward their partners.

"What do you intend to do with Dang Seorin?"

"If you're planning to dispose of Dang Seorin after we're dead, then I absolutely won't kill myself for you. Not under any circumstances."

An ominous atmosphere spread at once.

But I shook my head lightly.

"No. You needn't worry about that."

"...?"

"Of course, when you die, your Dang Seorin will be left alone."

I firmly took Dang Seorin's hand. I could feel her looking at my profile, but for now I focused on the Undertakers.

"But Dang Seorin never simply wanted to travel. She wanted to travel 'with me.'"

"..."

"So when you're gone, the Dang Seorins will naturally disappear as well. Trust me."

Silence fell.

Then someone spoke.

"I'll trust you, No. 107."

That, too, was me.

Parallel worlds. Possible worlds. The multiverse.

Leibniz is known as the first philosopher to propose such concepts. Yes, the man who fought with Newton over who invented calculus first (not that anyone studying for entrance exams cares).

One concept somewhat less well-known than calculus is the “best of all possible worlds.”

"Our world is the 'best of all possible worlds,' and therefore the only one that exists."

Why do we live in this particular world, rather than another worldline?

In other words, why does the world we live in look the way it does?

"Because our universe is better than the other worldlines."

The best of all possible worlds.

Something is wrong with every other world. Their physical laws might collapse, or an unimaginable evil might arise.

Even if our world feels like shit, it is nevertheless the only place where the “failure of the universe” has not occurred.

"I lose."

And we, the Undertakers, began the task of selecting the “best of all possible worlds.”

"You're a step ahead of me. You were the first to suggest using the Saintess's Telepathy, and the first to realize we nearly fell into the gu-poison trap. It's only right that I step aside."

The Undertaker who said he had boarded the plane fifty-sixth accepted his exit without fuss.

He took Dang Seorin No. 56's hand.

"I'm sorry, Dang Seorin. It looks like we'll have to put off our trip until next time. I'm truly sorry."

"Mm. It's all right. Just being together was enough."

Then an astonishing scene unfolded.

Undertaker No. 56 and his Dang Seorin embraced and kissed as naturally as anything.

"Ack."

"Mm."

The original Dang Seorin and I were both startled. What was this shameless display in broad daylight?

Watching someone who looked exactly like me lock lips with someone who looked exactly like Dang Seorin stirred exceedingly, exceedingly strange emotions.

"Huh?"

But there was something even more astonishing.

Of the more than one hundred passengers, we were the only two who had been startled.

"What are you so surprised about?"

"Yeah. They can kiss. What's the big deal?"

That's right. None of the other Undertakers or Dang Seorins seemed particularly moved.

But there was something even, even more astonishing.

"What's wrong with a couple kissing?"

"Exactly. We ought to restrain ourselves in front of other people, but you're all 'us' anyway."

"We've all seen each other at our best and worst. Why make a fuss over a mere kiss?"

Every Undertaker and Dang Seorin gathered here was dating their partner.

Except the two of us.

"Good heavens."

"Good God."

In short, this plane was a charter flight for a group couples' vacation.

Apparently, the other Undertakers and Dang Seorins had planned overseas trips to celebrate their first, third, or tenth anniversaries.

Again, except the two of us.

The top of my skull began to tingle. How could such a thing happen?

"No, we're the ones who are surprised..."

"You're really not dating? Me and Undertaker?"

"Why? Why on earth aren't you dating?"

On the contrary, the other couples seemed unable to understand us.

"If you're not dating, why did you go on this trip?"

"Well. That's..."

"I just said I was craving a trip," said Dang Seorin the Original.

"We set off two days after I brought it up. That's where we are now."

"Two days? Your destination is that terrifying Uyuni desert, and you went just because she asked? Even though you're not dating?"

"Yes. Is there a problem?"

"Huh..."

The Undertakers and Dang Seorins stared at us as though they'd encountered the strangest people imaginable.

"Aren't you two the abnormal ones?"

I didn't bother answering that question.

Despite that minor incident, the task of selecting the “best of all possible worlds” proceeded steadily.

The tests took all manner of forms.

"I'll settle this by the sword. No. 107. If you're stronger than me, I'll hand this life over without complaint."

Sometimes, martial strength.

"Ultimately, knowledge is what matters most to a regressor. In particular, how to help our companions grow and how to defeat anomalies. No. 107. Let us pit our knowledge against each other."

Sometimes, intellect.

"Even with a sword that cleaves the earth and a mind that mocks the heavens, you're destined to be devoured by anomalies the moment you break mentally. No. 107. How far can you preserve your sense of self?"

Sometimes, mental fortitude.

"I don't intend to drag this out like the others. Luck. Luck alone. Let's settle it with a simple coin toss. No. 107. Heads or tails?"

Sometimes, mere luck.

"Was Jiang Wei right to persist in his northern expeditions in Romance of the Three Kingdoms?"

Sometimes, just Romance of the Three Kingdoms... Wait, are you really all right with that? The Dang Seorin beside you is looking at you as though she wants to kill you.

Anyway.

The fifty Undertakers each requested a contest in a form they could accept.

I overcame every one of those challenges.

In the end, there was no “me” stronger than me. That fact saddened me, even as it made me proud.

"... In the end, was it my role as a regressor to decide which world was best?"

The Undertakeress smiled bitterly.

All the other regressors had accepted their ends. She was the last remaining “me.”

"I prided myself on having lived as diligently as I could, but even that wasn't my very best."

Unusually, the Undertakeress had challenged me to a game of Go.

A human game that had already surrendered the title of strongest player to AI. A field in which one's skill was judged by how closely one could imitate AI's tactical calculations.

Thus, it was also an ideal arena for evaluating Perfect Recall.

Across countless runs, I had “remembered” countless records of Go games. To me, Go was nothing more than a game of applying memories.

In other words, the Undertakeress had challenged me to see which of us was better at processing memories.

In a sense, that could be called a regressor's most important field—and virtue.

It was difficult to distinguish which of us was the stronger player.

The result was:

"Well played."

"Thank you for the lesson."

White won by half a point.

A narrow victory for me.

"I'm sorry, Dang Seorin. It looks like we'll have to postpone our trip to Oxford."

"It's all right. We can go 'next time' anyway."

The Undertakeress's partner, Dang Seorin, gave a little smile.

"But are you really all right with this?"

"I am. It was a result I can accept. Above all, just learning that the 'me' in another possible world is working equally hard is a great gain. I can't lose to myself."

"You just did."

"I mean from now on."

The Undertakeress took her Dang Seorin's hand.

Then she turned toward me with a faint smile.

"I entrust this world to you, No. 107. We will probably never meet again. If I'm a real human rather than an anomaly, I'll return to my world and be sure to give the Saintess a pair of sunglasses."

Aura enveloped the Undertakeress's entire body.

That was the end of “Undertaker.”

There is an epilogue.

Our original itinerary should have taken us to South America by way of Spain.

Yet, for some reason, not long after all the Undertakers had exited, the plane reached its destination.

The Uyuni desert.

The most radiant mirror on earth.

"Ah."

The plane landed gently on the water.

There was no vibration at all.

Its wings grew wet as they sliced through the desert's transparent surface. A long trail stretched across the water behind its tail.

Even then, quite a few “Dang Seorins” remained. Some had taken their own lives as though following their Undertakers, but others had stayed beside their Undertakers' bodies.

The door of the plane, which had neither crew nor pilot, opened. The sunset reflected in the desert's water spilled into the cabin.

"It's beautiful."

"Yes. Beautiful."

"I think I understand why I wanted to come here."

"How can the world be so beautiful merely by being reflected—"

They slipped away.

The Dang Seorins could say no more.

The moment the outside world's sunset touched them, their bodies turned into white salt and poured down in an instant.

The pure white powder scattered, swept apart by the desert wind.

It wasn't just the Dang Seorins. The Undertakers' bodies, the shattered plane seats, and finally the plane's enormous frame all crumbled into whiteness.

Like flower petals.

Before we knew it, only Dang Seorin and I remained in the middle of the desert lake.

"..."

Dang Seorin gazed blankly up at the circling dance of white petals.

Each petal reflected the red of the sunset, and their reflected shadows were reflected once again on the horizon.

In a world where everything repeated, only the warmth where our palms touched was unique.

Only much later did Dang Seorin murmur,

"What was that anomaly, really, Undertaker?"

"That sort of..."

"Spare me the bit about how eliciting that sort of reaction is exactly what makes it an anomaly."

"Mm."

I looked out over the salt desert made from the remains of Dang Seorins and Undertakers.

"There must be several interwoven causes, but the explanation that comes to mind is that it arose from the terrain of the 'Uyuni desert' itself."

Dang Seorin tilted her head. Her reflected shadow on the water beneath her feet tilted its head in turn.

"This place? Why?"

"When the water rises here, the whole place becomes one enormous mirror. As you know, mirrors are the most dangerous objects in the void. We intended to come to the Uyuni desert, but in a sense, we ended up going to a 'mirror world.'"

"Ah."

"A plane is a means of traveling to 'somewhere other than here.' The plane we boarded briefly took us into a mirror world."

"I see... Yes, that sounds plausible."

SPLASH

Dang Seorin swept her foot through the water. Her smile was captured in the rounded droplets that leaped into the air.

"Anyway, that means my Undertaker was the best Undertaker, right? Doesn't it?"

I didn't bother answering that question.

"I really love it here. Thank you, Undertaker."

"You're welcome."

"Oh, but how do we get back to the Korean Peninsula from here? The plane just melted away."

"..."

That question, I couldn't bring myself to answer.