Chapter 104
...This is some pretty difficult information.
"What is the matter, Thor-sama?"
This is my workshop in Raizenga territory.
While I was pondering the documents, Mabel brought me some tea.
"If something's troubling you, I can listen..."
"Thanks, Mabel. Then, will you hear me out?"
There was no point in doing nothing but worrying.
Sometimes talking to someone helps organize your thoughts.
So I decided to tell Mabel about it too.
"While clearing out the warehouse, I found some material from another world."
"A book like the 'Mail-Order Catalog'?"
"That would have been nice. Unfortunately, what I found this time was only a page torn from a book."
I placed the material in front of Mabel.
It was a battered sheet of paper. The writing had faded, and parts of it were unreadable.
It was written in the language of another world. There was no doubt that a hero had brought it here.
But only part of it could be deciphered.
That's how ancient documents were, but... what a shame.
"This... shows a starry sky, doesn't it? What is this large sphere? I can see clouds and seas on its surface."
"Apparently, it's a picture of a planet from the Hero's world."
"A planet?"
"More precisely, it's the planet the hero lived on. Apparently, they photographed it from an extremely high altitude."
The Hero's world was a sphere, with vast seas on its surface.
It was incredibly mysterious and beautiful.
Perhaps Mabel was thinking the same thing. She stared intently at the photograph.
"The hero from another world could fly this high...?"
"The hero's flying magic is what's truly terrifying..."
Mabel and I nodded as we stared at the material.
"So this is the world the hero came from... Does that mean this is an explanatory book about the Hero's world?"
"Not exactly. It talks about how the universe came into being."
"The universe... meaning the world of the starry sky...?"
"I only deciphered part of it, but... according to this material, the starry world is unimaginably vast. The land where living things exist orbits the sun, and beyond it stretches infinite darkness."
"So that's what the Hero's world was like..."
"Maybe this world is like that too."
"...It could be."
Research into the starry world had not progressed very far in this world.
Everyone was too busy dealing with things on the ground.
There were wars between nations, and monsters too.
At most, people used the positions of the stars to determine where they were and which direction they were facing.
After all, the Dorgalia Empire, the greatest power in the world, believed that 'strength was the most important thing.'
They completely neglected the starry world.
Originally, that sort of research should have been done by alchemists who explored the mysteries of the world.
Maybe I should conduct some research myself once I had more time.
"If the starry world is really that vast, maybe there are demons, demi-humans, and other creatures besides humans somewhere in the sky."
"According to this material, no such things have been found yet."
"Really?"
"Apparently, the starry world is simply too vast. Even traveling at the speed of light, it would take years to reach another sun."
"Light travels incredibly fast, doesn't it?"
"It sure does."
"For example, if you stood on a mountain and used the 'Light' spell, people at the foot of the mountain could see it right away."
"That's right. So even traveling at that speed, it takes years..."
"I can't even imagine how vast the starry world is."
Mabel and I sighed.
If the starry sky in this world were like that of the Hero's world, then──it must be incredibly vast.
I had no idea how long it would take to investigate it from one end to the other.
The starry world was full of mysteries.
It was beyond me as an alchemist. Fascinating, but impossible to investigate completely...
"Still, the starry world is so romantic."
"It is."
"Thor-sama... If you'd like, shall we gaze at the stars together tonight? I'll prepare some warm tea and blankets. How about putting chairs outside and relaxing?"
"Sounds nice. Let's do it."
"Thank you."
Mabel nodded, her eyes shining.
"Now that we've learned the secret of the starry world, I'd love to discuss it with you at leisure, Thor-sama..."
"About that secret of the starry world..."
"Yes, Thor-sama."
"I actually found some other material too."
I took another sheet of paper down from the shelf.
This was another page from a book from the other world. Like the previous material, it was in very poor condition.
But it too contained something related to the starry world.
"This talks about a sun other than the sun in the Hero's world."
"The sun that takes years to reach even when traveling at the speed of light?"
"No, one even farther away. It says, 'a sun one hundred light-years away.'"
"...That's a distance beyond imagination."
Mabel had a blank look on her face.
Right. The starry world was far too vast.
According to the previous material, the starlight we saw was apparently light from several years ago.
The distance was so great that even the light took years to reach us.
I couldn't even imagine how vast the starry world was, but──
"Then what is on that 'sun one hundred light-years away'?"
"Well, it says that the 'Gorongalagong aliens,' who came from a planet near that sun, are building a vast underground empire beneath the Hero's world."
"...Huh?"
"That happened thousands of years ago, and the 'Gorongalagong aliens,' who tried to conquer the surface, fought the ancient people of the Hero's world and were driven underground. But apparently they still seek to conquer the surface. The ruins found throughout the world are actually entrances the 'Gorongalagong aliens' use to observe what's happening aboveground, and now, at this very moment, the time of their revival──"
"Please wait, Thor-sama."
Mabel shook her head in confusion.
I understood how she felt.
"According to the previous material, it takes years to reach another sun even when traveling at the speed of light, correct?"
"That's right."
"Then how can the 'Gorongalagong aliens' come from a 'solar system one hundred light-years away'?"
"But... that's what the Hero's world material says."
I pointed to the page and read aloud the words written there.
Only a few of the words could be deciphered.
But they contained astonishing information.
'──Aliens have come to Earth.'
'──The threat of a terrifying underground empire!'
'──Traces of aliens... in ruins remaining throughout the world...'
There was something that looked like a photograph or a drawing too, but unfortunately, it was fading away from age.
The writing itself was compelling. I couldn't believe it was a lie.
But──
"These two pieces of material contradict each other..."
"One is about the vastness of space, which we still can't cross, right?"
"Yeah. The other says, 'Cover one hundred light-years in a single leap with supertechnology.'"
"Does that mean one of them is wrong?"
"One matter-of-factly describes the vastness of space. The other has this intensely urgent tone and describes the threat of the 'Gorongalagong aliens.'"
"Clearly, they were left behind by different people."
"Which one do you think is correct, Mabel?"
"The 'Gorongalagong aliens.'"
Mabel nodded.
"Because the hero summoned from another world was incredibly strong."
"Yeah. I get it."
"If the people of the Hero's world had been fighting the 'Gorongalagong aliens' since ancient times, it would explain why the hero was so strong. Since they had constantly faced threats from the starry world, perhaps that's why the hero continued striving to become the strongest after coming to this world."
"Exactly..."
That's right.
If this material was correct, it explained why the hero from another world had been so strong.
I didn't know what the 'Gorongalagong aliens' were like, but they were probably beings completely unlike us.
They lived in a place a hundred light-years away. That was beyond merely being from another world.
Their appearance, language, and even their way of thinking could all be different.
If people had been fighting such creatures since ancient times, it made sense that the hero was so strong.
Thinking about it that way also explained why the hero summoned to this world had adapted so easily.
Compared with the 'Gorongalagong aliens' one hundred light-years away, people from another world were practically next-door neighbors.
Being summoned here probably wouldn't have surprised the hero at all.
...This was a problem.
If I accepted the existence of the 'Gorongalagong aliens,' I could understand why the hero had been so strong.
What a terrifying presence those 'Gorongalagong aliens' were...
"But you think the 'matter-of-fact universe' material is the correct one, Thor-sama?"
Mabel suddenly said that.
"...How did you know?"
"To serve you properly, I make sure to pay attention to your expression, Thor-sama."
"You're perceptive."
"But it's strange. If the material about the 'Gorongalagong aliens' is correct, wouldn't it explain many things about the Hero's world?"
"But there's one thing I don't understand."
"Something you don't understand?"
"The hero summoned to this world never mentioned the 'Gorongalagong aliens' at all."
"...Oh."
Mabel's eyes widened.
It seemed she had realized what I was thinking.
If the otherworldly hero had really spent all that time fighting aliens—or underground people—then naturally, the hero would have left some mention of it.
They might have said things like, 'Compared to the Gorongalagong aliens, this monster is nothing!' or 'Take this! The ultimate spell that can defeat even the Gorongalagong aliens!' as catchphrases.
But the hero had never said anything like that—not even once.
It was impossible that those heroes, who single-mindedly sought to become the strongest, would never mention the invaders of their own world—in other words, their rivals. They were a terrifying fighting force, the kind who would even rejoice at finding worthy opponents among the Demon King's army.
Besides, the magic the otherworldly heroes excelled at was Light and Fire magic.
But if they were fighting people who had built an underground empire, then Earth magic should have been important. It could be used to dig through the ground and was also useful for sealing entrances from underground.
Yet the heroes disliked Earth magic, dismissing it with a single word: 'dull.'
Surely they had their own aesthetic principles they refused to compromise on.
But if they had been fighting underground people, then it would have been more natural for them to learn powerful Earth magic. It was impossible to imagine those heroes putting off magic that was effective against their enemies. They had leveled up with maximum efficiency, hunted monsters, and fought demons and demi-humans.
Taking all that information together──
"We should conclude that this material is wrong, and that there were neither aliens nor underground people in the Hero's world."
"As expected of you, Thor-sama."
Mabel nodded repeatedly, as if satisfied.
"It certainly is strange that the heroes left behind no mention of the 'Gorongalagong aliens.'"
"Then the 'matter-of-fact universe' material must be the correct one."
"That's a relief. There were no evil aliens coming from a distant star..."
"That's right."
"Now I can gaze at the stars with you without worrying, Thor-sama."
I could understand why Mabel was relieved.
If I thought aliens might invade from beyond the stars, I wouldn't be able to calmly observe the heavens either.
"Maybe the material about the 'Gorongalagong aliens' is an excerpt from a story."
"That's right... Now, about the third piece of material..."
"There's more?!"
"The next material is about ruins in the Hero's world."
I placed the third sheet of paper on the table.
It showed stone structures.
"Apparently, the Hero's world had structures that the sun passed directly over only twice a year, as well as ruins for measuring the positions of the stars. The sun and the starry sky must have been important there too."
"Is that so?"
"Maybe that was the secret behind the otherworldly heroes' strength."
"Then perhaps we should research the starry world here too."
"Yes. I'll ask His Majesty the Demon King whether I may create items for observing the stars."
"It might be a good idea to build a facility for observing the sky as well."
"An observatory... Yes, I think so."
I decided to write a letter to Demon King Lukie.
For now, I would tell him about items for observing the stars and about the observatory.
And... just in case, maybe I should send the three pieces of material along with their translations too.
Thinking that, I began my preparations.
──A few days later, at the Demon King's Castle──
"Kelv."
"Yes, Your Majesty."
"Thor has submitted a request to build an observatory. What do you think?"
This was the throne room of the Demon King's Castle.
Demon King Lukie held a parchment as he faced Chancellor Kelv.
"According to him, observing the stars might help him understand the hero."
"By observing the stars?"
"That's right."
"In that case... perhaps he wants to build a watchtower under the pretext of building an observatory."
"A watchtower?"
"Thor-dono would certainly be capable of creating an item that can see far into the distance. If he built an observatory equipped with such an item in the mining region of Raizenga territory, it could be used to keep watch on the Empire. Preparing for threats from foreign countries—that may be Thor-dono's plan."
"Would he think of something so sensible?"
"Perhaps he does once a year."
"The letter also contained documents from the Hero's world, along with translations."
"From the Hero's world? What did they say?"
"It said, 'Since these are valuable, please read them together with the chancellor.'"
"Understood. Then, if you will excuse me."
Chancellor Kelv rose and moved to the side of the throne.
Thus, Demon King Lukie and Chancellor Kelv began reading the 'documents about the universe' from the Hero's world, but──
"──Hmm, hmm."
"──I see."
"............So this is what a star looks like..."
"............This has military potential..."
"........................The universe. Planets..."
"........................An invasion?! From beyond the stars?!"
"..............................So they've been observing the stars since ancient times in that world? How romantic..."
"....................................An underground empire?! Terrifying aliens from outer space?! No, Thor-dono's analysis says that's wrong... But still............Hmm..."
"I see. It sounds interesting. We may as well approve the observatory."
"Y-yes, indeed! We shall permit the construction of the observatory. It's not that I believe in aliens or anything... Learning about the world is a worthwhile pursuit. There are no aliens, of course! None at all!!"
Thus, the ruler of the Demon King's Domain and his chancellor approved the construction of the observatory.
Demon King Lukie grew interested in the universe, while Chancellor Kelv decided to seal the second article as dangerous information.
Accordingly, Thor would use the 'Hero Catalog' as a reference to create a 'telescope,' but──
As a result, a few years later, astronomy in the Demon King's Domain would undergo tremendous development, and researchers from other countries would come seeking instruction... but for now, no one knew that it would happen.
Side Story: Thor, Mabel, and Forbidden Astronomy—The End.