Humm...
The Astral Express slowly came to a halt before a hidden palace shrouded in a barrier.
An elf dressed in a plain short robe, barefoot, with flowing golden hair, slowly sat up.
Beside the throne, thousands of magic books were piled up in disarray—far more than any ordinary person could ever hope to master in a lifetime.
The elf was petite, her expression lazy, her attire exceedingly simple.
Yet anyone who wielded magic could sense the immense power radiating from her.
Even with her magic suppressed, the power emanating from Serie was enough to rival Frieren at full release.
"Oh..."
She stepped out of the hall and looked up at the strangely shaped Astral Express.
Whether from her own perspective or that of humans, the thing was far too advanced.
"Hello, we are from the Starsea Empire."
Himeko was the first to step off the train and greeted Serie.
"I know who you are."
Serie's gaze drifted between her and the train.
"You appeared out of nowhere in this world, threw all the nations on the continent into chaos, and even turned the Demon King's army upside down."
"Oh, and you even captured the Demon King and those great demons? Interesting."
Serie glanced toward the carriage, where several unfortunate demons were trapped in force-field cages, being experimented on by Herta and Ruan Mei.
She was a great mage who had lived since the mythical era, possessing nearly all human magic, and the closest being to a god on the entire continent.
Her strength was more than enough to defeat the Demon King and his army, yet she had no interest in doing so. Whether the continent prospered in peace meant little to her.
She even preferred that war continue, so that magic could keep evolving—and to entertain herself.
"So? You've thrown this world into chaos and captured the Demon King who was supposed to be defeated by a Hero. What exactly do you want?"
Serie's tone carried a hint of laziness.
"This world will soon be incorporated into the rule of the Starsea Empire. We will establish a unified administrative body here."
"And we will elevate this world's technological level from the feudal era to the spacefaring age as quickly as possible, managing it as a vassal world of the Starsea Empire."
Sophon replied.
"Huh?"
Serie's expression turned a bit strange.
She didn't care about wars among humans. Every so often, some ambitious and capable ruler would rise and unify most—or even all—of the continent. That was nothing unusual.
But conquerors from another world? That was something else entirely. Their technological level was on a completely different plane from the natives.
Conquering the entire world would likely take them only a few days.
"The Commander invites you to join the Starsea Empire. Your talents are well suited for the Empire's Magic Department."
Himeko said.
"?..."
Serie looked at her, then at the Astral Express, unable to sense even the slightest trace of magic.
"But it doesn't seem like you can use magic."
"Is that so?"
Setsuna jumped down and looked at the small elf with amusement.
Like Frieren, she looked young, but was in fact an old monster.
"Make a wish. Whatever you want, I'll give you one thing—as a greeting gift."
"Oh?—"
Serie examined Setsuna again. She still couldn't sense any magical aura, but her instincts told her this man was anything but ordinary.
"Anything?"
"Most things you can see or imagine."
Setsuna didn't mind demonstrating his power.
"Hmm..."
Frieren's grandmaster fell into thought.
"I want an Imperial Dragon... no."
She had originally intended to request some kind of monster or dragon to make things difficult for him, but when she looked up at the sun, she raised her hand and pointed.
"The sun."
"?"
"Are you deliberately making things difficult?"
Frieren froze for a moment.
"Testing others with something you yourself can't achieve isn't a good habit."
"Ah, I was just saying it casually..."
Serie waved it off with a laugh. But before her words had even fully fallen—
"Sure. Then watch closely."
Setsuna raised his hand. Imaginary energy and Honkai energy gathered within his palm.
A small fireball formed, initially about the size of a lump of dough, radiating orange-yellow light and heat.
"This is...?"
Serie's expression turned serious.
Whoosh—
With a flick, the fireball shot upward, rapidly expanding. Its brilliance grew blinding, and the surrounding temperature surged dramatically.
If it hadn't been moving away from the planet fast enough, the heat it emitted would have turned the entire surface into molten lava.
The miniature sun soared farther and farther away, breaking through the atmosphere in an instant and entering outer space.
Its size expanded violently as well, stabilizing millions of kilometers from the planet—transforming into a blazing star.
Looking up, even in broad daylight, a second sun had appeared in the sky.
Setsuna had positioned it carefully so as not to disrupt the gravitational balance of the star system.
Even so, the air temperature rose by several degrees, and the sunlight grew noticeably stronger.
"???"
Serie and Frieren were both stunned.
When they looked at Setsuna again, it was no different from gazing upon a creator god.
What kind of magic was this? Creating a sun out of thin air?!
Even as a "walking grimoire," Serie had never heard of such an absurd spell.
In an instant, Serie—who had always viewed magic as a tool for combat—realized something terrifying:
If Setsuna hadn't thrown that miniature sun far into space, but instead created it directly on the surface, it would have been enough to destroy the entire planet in an instant.
"..."
She stared at the sky for a long time, unable to recover, until the sunlight stung her eyes and she finally shook her head, lowering her gaze.
"How did you do that? Is it magic from the mythical era? I don't recall ever seeing it."
"A star is essentially a massive nuclear fusion reactor. Once you understand its nature, recreating it isn't difficult."
"Someone once asked me for a pink star. Your request was much simpler than hers."
Setsuna chuckled.
"But I don't plan to keep this new sun for long. It would interfere with the climate here."
As he spoke, he looked at Serie.
"Any other questions?"
"..."
Serie stared at the two suns in the sky, silent for a moment.
"Give me an hour. I need to pack a few things."
...
Swish—
When the Astral Express set off once again.
Serie sat in the observation carriage, curiously observing everything around her.
"Oh..."
"Is this a means of transportation you created using flight magic? Impressive."
She looked at Pom-Pom wandering around the carriage with great fascination.
"A familiar you summoned? Or some other kind of creature?"
"Pom-Pom is the conductor, Pom! Put on your shoes—don't walk around barefoot in the carriage!"
Pom-Pom frantically complained about this barefoot mage.
"When can you take me to your country?"
Serie asked.
She had spent far too long as a godlike existence in this world, mastering nearly every form of magic imaginable.
Setsuna's appearance made her realize that beyond this world, in places far more distant, there existed things far beyond her comprehension.
Magic on an astronomical scale was fundamentally different from what was practiced on land.
She wanted to see those new things.
"Hmm... you'll have a place in the magic academy in the future. Those Crimson Demon girls would be perfect students for you to teach."
"As for magical systems from different worlds, you might need to spend a few thousand years studying them before you fully understand."
Setsuna checked off an item on his list and looked at Frieren and Serie.
"But we still have some things to do in this world."
"Don't you feel like your master's lineage is missing someone?"
"You mean Flamme?"
Serie looked into the starry sky, her expression distant.
"That... was over a thousand years ago."
Both she and Frieren were elves with long lifespans, but Flamme had been human—her life lasting only a few short decades before returning to dust.
Although Serie often claimed she didn't get along with that disciple, Flamme was still her adopted daughter. There was, inevitably, a trace of longing.
"I quite liked her. In the future, she'd make an excellent teacher at the magic academy."
Setsuna said.
"Now, let me show you another miracle worthy of being called magic."
"Let Flamme see what you—and this world—will look like a thousand years later."
"What?"
Before Serie could ask more—
Swish—
The hyperdimensional starship unfolded within the starry sky. Everyone's perspective was stretched into higher-dimensional space.
Moving backward along the axis of spacetime, the cosmos reversed before their eyes. The world was pressed into rewind, and time on the planet began to flow backward.
Elderly people at the end of their lives reverted into vigorous youths, then in the blink of an eye became infants wrapped in swaddling clothes.
Towering ancient trees shrank into newly sprouted shoots. Rivers changed course. Mountains shifted.
Flora, fauna, birds, beasts, fish, and insects—everything in the world reverted to its previous states.
"This..."
Faced with such power to reverse time, Serie and Frieren were left speechless.
Even at the limits of their imagination, it was difficult to comprehend what kind of power was required to traverse over a thousand years.
"We've arrived."
Click—
In just a few breaths, the ship detached from the spacetime axis and returned to the universe.
The continent's environment and nations had changed somewhat, but overall it still retained the appearance of the medieval era.
In the northern part of the continent, near a simple cabin within a forest.
A female mage with long orange hair tied into a thick braid, wearing a white robe, planted a small sapling into the ground.
She also used magic to set up a protective spell for it.
"Once this little one grows up, it will continue to protect this place—even a thousand years from now."
The mage's movements were gentle yet resolute.
"...By then, Master, you'll already be dead, right?"
Beside her, a young elf girl with still somewhat immature features asked.
"But you won't."
Flamme smiled at her.
"One day, you'll make a grave mistake and come to understand humans."
"When that time comes, return here."
"..."
"Mm."