Crossover Shipgirls: Building a Dimensional Empire from Scratch

”I’ll give you a set of materials. Read them when you have time. The history of the Starsea Empire, along with information on its various races and members, is all inside.”

After roughly settling them into the residential district,

Setsuna summoned a few Angeloids and handed Tiamat, Ishtar, and the others each a tablet containing the stored data.

”Yes, Master.”

The angels nodded respectfully, signaling for everyone to follow them.

”Next, I will guide you through the Starsea Empire on Master’s behalf.”

”We will board a small shuttlecraft. The expected duration for our first stop—Earth—is 5 hours and 32 minutes. Afterward, we will proceed to other star systems for observation according to your individual interests...”

The Angeloids precisely mapped out a sightseeing route for them. The goddesses listened with great curiosity.

Especially Ereshkigal. Having suddenly come from the Underworld to the capital of a super empire, her eyes were dazzled by everything.

She could hardly wait to follow the angel and see it all at once.

One after another, they boarded the ship behind the Angeloids.

”Mm...”

Only Tiamat remained where she stood, unmoving.

”Please board the shuttle with me. I will take you to tour the Starsea Empire.”

The Angeloid bowed respectfully and invited her once more.

”No... not right...”

Tiamat puffed her cheeks and tugged at Setsuna’s sleeve.

”...They are not human.”

”Oh, Angeloids are artificial intelligences—mechanical creations of engineering. Many tasks and combat missions in the Starsea Empire rely on them.”

”Don’t worry. They’re very intelligent, and their piloting skills are excellent.”

Setsuna assumed Tiamat had some issue with the Angeloids.

”I don’t want... robots.”

”I want to stay with Master... that is correct, isn’t it? Because you are my... child.”

Tiamat’s voice was earnest, but to Setsuna it sounded like she was acting spoiled.

She refused to let go of him. Perhaps her earlier abandonment had been too painful—Tiamat seemed unwilling to let him leave her sight at all.

”No, how does she manage to overflow with maternal instinct while also casually acting cute and asking the Commander for cuddles?!”

Gudako stared in disbelief.

”You’re right. That’s Tiamat.”

Setsuna sighed.

He projected a small shuttle and stepped into the cockpit.

”Come on. I’ll take you myself.”

”...Good child. Mother... is very happy~”

Tiamat squeezed into the seat beside him.

She adjusted her hair, sitting upright and proper.

A strange little tune even slipped from her lips.

”Aaa... la... Aaa...”

”...?”

The other goddesses exchanged glances behind them.

Could a ”Beast” feel happy? Apparently so. Ever since arriving in the Starsea Empire, Tiamat had been in high spirits.

Hummm—

The shuttle flew forward, weaving through countless floating architectural clusters.

The prosperity of an interstellar metropolis far exceeded the comprehension of any pre–Common Era native.

No matter how they tried, they could not imagine anti-gravity structures stretching from the ground into the clouds, or angels and starships traversing the skies in sleek arcs.

”This is the capital of the Starsea Empire. Most people who come from other worlds live here.”

”In Golden Horn Bay is the shipgirl port district. Some of them also stay at the Starbase. Over there is Chaldea’s residential area—companions from other Singularities are gathered there.”

”Oh, those little ones who all look the same, cute, carrying wrenches, drills, and hammers? Those are Bulins. Most things in the Starsea Empire are crafted by Bulins.”

”...”

Setsuna introduced the general layout of the capital one by one.

Tiamat leaned toward the viewport, watching the city below without blinking. Most of her attention was focused on the various forms of ”life.”

Horse girls, cat girls, ordinary little girls—these all fell within Tiamat’s understanding of ”life.”

As for shipgirls, Angeloids, and even outer gods of Cthulhu... they were something on another level. Theoretically life, yet somehow strange upon closer thought—beyond Tiamat’s knowledge.

”Don’t casually use your authority in the capital. Shipgirls and angels might endure black mud, but ordinary people can’t. There are Seiren from the No Game No Life world living under the sea. If you pollute the ocean, they’ll be done for.”

Setsuna reminded her again.

”Mm...”

Tiamat looked aggrieved.

”I won’t... They are your children... and also my children. I will... take care of them...”

”What makes you unhappy... I will not do.”

Whoosh—

After circling the capital once, the shuttle ascended and began touring other regions.

Earth had long been fully developed. The entire planet was a fusion of urban world and resort world.

Endless, sky-piercing interstellar cities coexisted with lush primeval forests and beautiful natural landscapes.

A perfect balance had been found between technology and nature.

”Not bad at all... Uruk—no, even all of Uruk can’t compare to a single street here.”

Ishtar clicked her tongue in wonder.

”Does it have a name?”

”It’s called Constantinople.”

Looking down, although the capital had originally developed from the old city, after years of expansion it had spread across the entire Eurasian continent.

Yet the name had been retained.

”Whoa, that’s a later-era city name, isn’t it?”

Ishtar thought for a moment.

”Constantinople... it has no aesthetic sense at all!! It doesn’t match such a beautiful city.”

”How about I come up with one? I’m not just the goddess of Venus—I’m also the goddess of beauty. Trust my taste!”

”Hmm?”

Setsuna blinked.

He had never paid much attention to the capital’s name. It had been used since the city’s founding.

Now that she mentioned it, it did feel somewhat lacking.

”Do you have any suggestions?”

”Call it Ishtar City. I preside over love, war, and fertility. Isn’t that perfect for Master? What do you think?”

Ishtar puffed out her not-so-large chest and volunteered eagerly.

”For ordinary mortals, naming a city after me would be the highest honor. But for you, Master, it’s fine...”

Thud—

Setsuna flicked her forehead.

”Your intentions are way too obvious. Rejected. We’ll discuss it later when we have time.”

Hummm—

After finishing the tour of Earth, the shuttle shot toward outer space.

”Wow...”

Gazing at the brilliant starry sky, Tiamat and the other goddesses fell into a daze.

Compared to an entire star system—an entire universe—even gods who ruled the Earth were nothing more than a drop in the ocean.

”With limited time, I can’t take you to every star system one by one. Let’s look around the solar system first.”

”This is the lunar research center. The headquarters of the Physics Department, Engineering Department, and Life Sciences Division are all here. If you’re interested, you can visit often.”

The shuttle descended into lunar orbit.

The Moon had been remodeled beyond recognition, covered everywhere in laboratories and research towers.

An artificial atmosphere surrounded the planet. Under climate control, it was no different from Earth’s environment.

”That is...?”

Tiamat’s attention was drawn to the Life Sciences Division.

Inside the experimental grounds, large numbers of Honkai Beasts were being cultivated, along with magical beasts brought from other worlds.

”Hmm... come to think of it, your abilities would suit this place very well.”

Setsuna considered for a moment.

”The authority of the Sea of Life would cause massive destruction on Earth, but on barren planets it could perform planetary transformation... no, something even more advanced than that. You can create life, right?”

Tiamat possessed the ability to grant life self-modification, ecological change, ecological fusion, and individual proliferation. She herself could evolve an entire ecosystem.

”...You mean Lahmu?”

Tiamat tilted her head.

”No, no, just normal creatures.”

Setsuna felt a headache coming on.

”If you directly remodel planets with your authority, you’d probably be even more efficient than the Engineering Department and the Magic Department.”

”Oh...”

Tiamat nodded as if she half understood.

”If you want... a new world... I will create it for you.”

”...I am very capable.”

Setsuna inhaled sharply.

Tiamat’s sincerity was unexpectedly lethal.

...

”The development direction of the Starsea Empire includes both the technological side and the magical side.”

”This area primarily focuses on engineering and physics research. The space warships you’ve seen, as well as the Galactic Wonders currently under construction, are all achievements of the Engineering Department.”

At the lunar research center, a group of pre–Common Era natives received a baptism of future technology.

”Uh...”

”In the myths of our era, teaching humanity how to use fire, farm, or herd livestock was already enough to be revered as a god.”

”If humanity were to reach this level in the future... then the end of the Age of Gods would be only natural.”

Ishtar was thoroughly convinced.

She realized that compared to interstellar-era technology, the power of a goddess lagged behind by more than a single tier.

”That’s just because you’re not strong enough. If you’re interested, you can enroll in the magic academy for further study.”

Setsuna smiled lightly.

”There are quite a few goddesses in the capital as well. If you’re willing, I can approve the construction of a grand cathedral for you to preach in the city.”

”Of course, how many followers you can attract depends on your own ability. At present, the goddess with the largest number of believers in the Starsea Empire is Eris. Do you plan to compete with the goddess of luck?”

”Huh?”

Ishtar froze.

”Forget it, forget it. I can’t provide followers with that many visible benefits anyway... and I’m not a faith-based god. I have no intention of absorbing faith.”

”Besides, this idea of believing in whichever goddess is most useful is just strange, isn’t it?!”

The newly arrived goddesses had initially shown some interest, but after learning about the Church of Eris and the other heavenly goddesses, they decisively gave up.

The reason was simple. A doctrine that provided immediate feedback and direct buffs to its believers was simply too overpowered.

Other vague, intangible religions stood no chance before a faith capable of manifesting miracles and embracing pure practicality.

After touring the research center, just as they were about to leave—

”So, we still have some free time. We could visit a few construction sites of Galactic Wonders, or would you like to explore other universes? ...”

”Commander, please wait!!!—”

A familiar voice came from behind.

A group of little girls from the Research Division suddenly surrounded him.

Standing at the front was a green-haired, green-eyed acquaintance wearing a lab coat.

Mobius.

She seemed to have rushed over from the other end of the laboratory, brimming with urgency.

Her gaze swept over Setsuna and the people beside him before finally settling on Tiamat.

”May I ask... are you the legendary Mesopotamian creator goddess, the Sea of Life, the one who holds the secrets of self-modification and life’s evolution—Goddess Tiamat?”

”??”

A question mark practically appeared above Tiamat’s head.

It was the first time she had received such an enthusiastic greeting.

”So it is you.”

The moment Setsuna saw Mobius and the Life Sciences Division’s little researchers, he understood most of it.

”You’ve only just joined the Research Division, haven’t you? Working on a new project on the Moon?”

”I’m continuing research into human and biological evolution. For example, adding chloroplasts to humans so they can photosynthesize and survive without eating...”

Mobius began rambling excitedly before shaking her head.

”No, no, that’s off-topic.”

”Commander, I roughly read the materials about the Singularity you expeditioned to. I don’t really understand things like Human Order or Holy Grails.”

”But!!! That creator mother goddess, Tiamat—her authority governs life and life’s evolution. She uses divine power to alter living beings.”

”There may be within it the secret to allowing organisms to evolve toward perfection on their own!”

Long before joining Fire Moth, Mobius had already achieved significant accomplishments in biological science, devoting herself to evolutionary research.

To her—and to the entire Life Sciences Division—Tiamat was practically a god.

The God of Life. The kind worthy of being enshrined by the Life Sciences Division.

”Please, could you let us witness the power of a god? I want to see... to what level life can evolve under divine authority.”

Mobius pleaded.

”Eh?...”

Tiamat seemed slightly at a loss and gently tugged at Setsuna’s sleeve.

”They want to see your authority. If you don’t mind, give it a try.”

Setsuna tilted his head in indication.

He was also curious how far Tiamat’s planetary remodeling had gone at the time of creation.

”Mm... if... my child needs me... then I can.”

Tiamat was delighted to be needed and readily agreed.

...

Half an hour later.

Whoosh—

The ship carrying Setsuna, his group, and the Life Sciences Division landed on Europa.

This moon of Jupiter had been largely preserved in its original state during the development of the solar system, deliberately left for various research purposes.

Its surface was covered in ice, with an ocean beneath.

There was also an artificial landmass where a modest research outpost stood.

”A new... world...”

Tiamat looked around. Europa was slightly smaller than the Moon and still desolate.

”To what extent can you remodel this planet?”

One little researcher asked curiously.

”...And you?”

Tiamat’s gaze shifted to Setsuna, her voice ethereal.

”What kind of world do you want? Anything... I can give to you.”

”Freely improvise first.”

Setsuna thought for a moment.

”Just as you did at the beginning of creation.”

”...Mm!”

Tiamat stepped forward, pressing both hands against her chest and raising her head.

”Aaa... Aa...”

As her chant echoed—

Shhh—

Beneath Tiamat’s feet, tide-like black mud suddenly surged forth.

Shhh—Shhh—

With overwhelming force, it spread outward.

Everything touched by the black tide was assimilated into it.

”This is the Sea of Life. It is also Tiamat herself.”

”All primordial life was born, evolved, and fused within this sea...”

When the Sea of Life enveloped the entire planet,

Tiamat’s transformation of the world began. This time, it was not ”regression,” but the reenactment of her authority as the creator of life.

Splash!!—

The Sea of Life churned and shifted before their eyes.

Mobius and the Life Sciences Division deployed observation instruments into the waters. The readings began fluctuating wildly.

”Life!!! Life is appearing out of nothing!!!”

Through advanced instruments, they witnessed life’s evolutionary process rapidly replaying within the Sea of Life.

It began with single-celled organisms—multiplying, evolving.

They transformed into primitive life forms with simple structures such as ferns, corals, and mosses, then twisted and reshaped into small arthropods.

Their evolution did not follow any traditional sequence. It was guided entirely by Tiamat’s will.

Soon, marine creatures grew limbs and climbed onto land from the Sea of Life.

None of these organisms matched any species recorded on Earth, yet faint shadows of ancient life could be seen within them.

”Ah, that’s Cambrian—no, Ordovician-era life?...”

”Acanthostega! That’s Acanthostega!! It’s reached the Devonian!!”

”Is that a Dimetrodon? Synapsids have appeared! That’s Carboniferous!”

The Research Division was stunned.

It was as though a grand cinematic epic were unfolding before them, recreating Earth’s evolutionary history across countless geological eras.

This was the authority of the Primordial Beast—the creator god.

Among the countless creatures that emerged from the sea and stepped onto land, some species possessed grotesque forms.

Their bodies were purple-black, roughly humanoid, with slender limbs and enormous maw-like structures atop their heads. They emitted eerie, cackling laughter that sent chills down the spine.

”Ah, I forgot. You don’t like Lahmu. I’m sorry.”

Tiamat paused.

Lahmu had been summoned when she previously returned to Earth, heralding regression.

To her, beauty and ugliness in living beings held no distinction—they were all born of her authority. Since Setsuna disliked them, there was no need to keep them.

She clapped her hands.

Fwoosh—

The Lahmu dissolved back into the Sea of Life, reshaping into other life forms.

Everyone watched clearly. Some Lahmu transformed into fish, others into bizarre reptiles, and some simply became seaweed-like plants. It was entirely arbitrary, utterly unreasonable.

Previously, being altered into a Lahmu had been a one-way, irreversible process. After regaining her rationality and intellect, Tiamat could freely return a species to the Sea of Life and reorganize it into another evolutionary form.

”Hiss...”

Mobius was beyond shocked.

”Are the appearance of all life, the process of evolution, and the final result... all determined by you?”

”Mm!”

Tiamat nodded.

”Whatever Master... likes... I can create.”

”A mother fulfilling her child’s needs... is only natural, isn’t it?”

—

—

40 Advanced Chapters Available on Patreon:

Patreon.com/DaoOfHeaven