Crossover Shipgirls: Building a Dimensional Empire from Scratch

At first, Setsuna was just teasing Akashi.

He hadn’t seriously expected to build a Gundam out of thin air.

Rome wasn’t built in a day. Before constructing a Gundam, a series of fundamental technological barriers had to be overcome.

But Akashi seemed to take it seriously. She holed herself up in her workshop for several days, buried in a mountain of design blueprints. Occasionally, when she emerged for fresh air, she’d mutter things like, ”I will deploy in Gundam form,” ”Unicorn will crush Strike Freedom,” or ”Turn A Gundam is invincible!”

She even stared at her own rigging with a pensive expression, sometimes breaking into a silly grin.

The other shipgirls thought she had broken down.

Finally, after days of tinkering, Akashi gathered everyone in the conference room.

With great fanfare, she declared her accomplishment:

”I’ve more or less figured out what the Commander gave me!”

”Huh?!”

The crowd reacted with varying degrees of surprise.

Setsuna’s eyes widened with curiosity. Despite her reputation as a greedy scammer selling repainted loot boxes, Akashi seemed to have real skills hidden beneath the surface.

The other shipgirls, however, were completely lost.

With a flick, Akashi projected a blueprint of a Gundam onto the screen.

”What’s this? A robot?”

Taihou tilted her head in confusion.

”This is what the Commander entrusted to me—technology from another world, meow!”

Akashi summarized succinctly.

Since Setsuna’s ability to open interdimensional portals was well-known, the shipgirls weren’t too surprised.

”Gundam technology is somewhat similar to ours—it’s based on engineering and designed as a weapon of war,” Akashi explained.

”However, these mechs lack independent consciousness and require a human pilot, meow.”

She first used language the shipgirls could understand to give a simple overview of Gundams.

”Who’s stronger—Gundams or us?”

Yukikaze immediately asked a provocative question.

”I’m not sure.”

Akashi scratched her head.

”If we’re talking about the strongest ones, like Turn A Gundam—Moonlight Butterfly, it’s said to have the power to destroy planets. But for a regular Zaku, it might not even be able to beat a Buli in melee combat—although they can fly, meow.”

”And Gundam’s combat capabilities depend heavily on the pilot’s skill. A rookie and an ace will perform very differently, meow.”

Hearing about planet-destroying capabilities, the other shipgirls grew solemn.

”Is this technology exclusive to the Commander?”

Richelieu asked as she examined the Gundam’s specifications.

In theory, shipgirls could pilot a Gundam. However, there was a glaring problem:

Most combat mechs weigh less than 100 tons, while shipgirls easily reach thousands or tens of thousands of tons.

Without rigging, it might work, but if they deployed their rigging inside the cockpit, they’d crush the Gundam from the inside out.

Additionally, it was hard to say whether a Gundam’s firepower could match the shipgirls’ overwhelming firepower projection.

”Gundams are primarily for the Commander’s use, but the technology can benefit all of us,” Akashi explained further.

”For example, shield generators, particle cannons, and propulsion systems can be modified to enhance our rigging, meow.”

The tech tree Setsuna had received wasn’t limited to just building a Gundam. It encompassed the entire foundation of the Gundam world’s science and technology, a colossal treasure trove of knowledge.

”Wow! Does this mean we can fly into space someday?!”

Several shipgirls lit up with excitement.

”Uh, that’s a bit tricky.”

”Formidable, considering your weight, even a Gundam’s propulsion system might struggle to lift you,” Akashi quipped, cutting off Formidable’s daydreams.

”What’s wrong with my weight?! Is it my fault my size is... well-endowed?! Some people are just jealous because they don’t have it!”

The affronted carrier shot back immediately.

”…”

”Alright then.”

Setsuna cleared his throat, bringing order to the room.

”Akashi, copy the technologies related to beam rifles, beam sabers, particle cannons, and anything else that can be integrated into rigging. Send it to the harbor for testing.”

”As for us, let’s pool our resources and try building a Gundam.”

The harbor had greater resources, making it a better choice to study advanced weaponry. Once completed, it could also be tested against the Sirens to gauge its effectiveness.

On Earth, however, Setsuna felt it was necessary to bolster his own combat capabilities. After all, if he turned out to be the weakest member of his team on future expeditions, that would be humiliating.

”Understood, meow.”

Akashi nodded, finding the plan perfectly reasonable.

”Commander, what kind of Gundam do you want?”

She continued, ”We can probably manage most mass-production models. Their weapon systems are similar to the ones we already use in the harbor—our naval guns are even bigger in caliber!”

”For specialized models, with enough time and resources, we could make units like the Unicorn Gundam, Strike Gundam, or Aegis Gundam… as long as their tech isn’t too outrageous.”

”Commander, do you prefer a long-range firepower type, a close-combat melee type, or one focused on defense?”

Each type had its own unique strengths.

Some specialized in large-caliber plasma cannons, while others boasted unparalleled agility, capable of sustained supersonic maneuvers.

Faced with a list of models, Setsuna hesitated, overwhelmed by choice.

After some thought, he finally spoke.

”Can you build me a Gundam with the long-range firepower of a battleship, the close-combat prowess to take down a Siren Arbiter, and the mobility to outperform a jet fighter?”

”…”

Akashi froze.

”Commander, are you trying to mess with me, meow?!”

Azur Lane World, Harbor

With the dimensional portal reopening, the Starsea Alliance began fulfilling the trade and research agreements signed with the harbor.

As compensation for the Vanguard Fleet’s assistance in building a new world, Earth regularly provided metals, petroleum, and other resources to the harbor.

This time, Essex returned with dozens of Bulins, bringing a massive haul of minerals to the port. Alongside them came the technological blueprints Akashi had copied.

”So much stuff?!”

Even Enterprise, the well-funded Eagle Union carrier, found the quantity of resources astonishing.

It was nearly equivalent to the harbor’s typical six-month resource consumption.

”We’ve further expanded the mining zone on the Balkan Peninsula. The resources on Earth are quite abundant,” Yukikaze declared proudly, hands on her hips as she directed the Bulins to unload the cargo.

”Especially now that there’s no one to compete with us. The entire world’s petroleum and rare metals are ours. Take as much as you like.”

While the harbor had large reserves, they were nothing compared to the resources of an entire planet.

Azur Lane’s world was primarily oceanic, and extracting underwater resources was an arduous task often disrupted by Sirens.

On Earth, the resource supply was only limited by how fast the Bulins and Manjus could mine and process it.

With just a few hundred individuals mining, they couldn’t deplete the reserves even if they treated oil like water and wasted ores like scrap.

”Wow…”

The shipgirls who had come to greet the fleet gazed in envy.

They had initially thought the Vanguard Fleet was venturing into a harsh and undeveloped world.

To their surprise, the conditions there turned out to be far better than expected.

”More importantly, the Commander hopes the harbor can expedite research on the new technologies,” Essex said as she handed over stacks of thick documents to Enterprise.

”Can you quickly manufacture these weapons and equipment, then test them in combat to evaluate their effectiveness?”

Enterprise flipped through the files out of curiosity.

The documents from Setsuna and Akashi described various weapons and equipment from the Gundam universe, such as plasma cannons, beam sabers, handheld energy shields, and propulsion systems.

The shipgirls had never seen anything like them before.

”Plasma cannons, I understand. But what’s a beam saber?! A melee weapon? Do we even need to study something like that?!”

”And what is this psycommu framework?! Controlling mechs with mental input?! Don’t we already have rigging and Wisdom Cubes?”

The research-focused shipgirls were utterly bewildered.

”Doesn’t Ayanami use a battleship blade? Once the beam sabers are ready, she can test them out,” Essex reasoned gently.

”Whether useful or not, there’s no harm in trying out each technology. If any of them turn out to be powerful, we’ll gain an advantage.”

Enterprise finally nodded in agreement.

”Alright, we’ll experiment with all of it. Be sure to thank the Commander for us.”

A Few Days Later – The Deep Sea

Far from the harbor, in the depths of the ocean, lay Siren territory.

Thousands of oddly-shaped, red-and-black unmanned Siren warships patrolled the waters, shrouded in black mist.

These Siren vessels ranged in class from destroyers to cruisers, battleships, and carriers.

Above the mass of automated ships hovered the regional leader—a Siren shipgirl named Purifier.

She lounged on her shark-shaped rigging, her long white hair tied in a ponytail, golden eyes staring lazily at the sky.

”Uh… so boring.”

Purifier stretched out under the sun.

Unlike shipgirls, low-level Siren ships lacked intelligence, leaving her stranded in the vast ocean with no one to talk to.

Usually, she had to find entertainment by bullying shipgirls in the harbor.

But with the stalemate in their war, neither side dared to make a decisive move, leaving Purifier bored out of her mind.

Suddenly, the Siren reconnaissance fleet sent out an alert:

”Warning: A fleet from Azur Lane detected 177 nautical miles ahead.”

”Fifty-five units, advancing at 30 knots toward our position.”

”?!”

Purifier instantly perked up.

”Hiding in your harbor, I might fear you a little. But you’ve got the audacity to come looking for trouble out here?”

”Ha! Did those shipgirls lose their minds?”

She immediately ordered her fleet to prepare for battle.

A fleet of 55 shipgirls was no small threat.

124 nautical miles…

87 nautical miles…

55 nautical miles…

The approaching fleet became visible on the horizon.

”Carriers, prepare to—”

Purifier froze mid-command.

Her outstretched hand hovered in the air.

Something about the approaching shipgirls felt... off.

To be precise, their equipment was unlike anything she had ever seen.

Leading the charge was the Eagle Union’s flagship, Enterprise, the strongest carrier.

Yet, she hadn’t manifested her rigging.

Instead, she wielded a massive, 2-meter-long crimson beam saber in her left hand and a glowing blue energy shield in her right.

Behind her, the rest of the fleet followed suit, brandishing similarly bizarre beam sabers.

”What the hell?!”

”Where are your riggings?!”

Purifier was dumbfounded.

She had been fighting these shipgirls for years, but she had never seen them use such tactics or weapons.

It felt like watching a phalanx of sword-and-shield warriors charge her fleet across the ocean.

”Charge!!!”

”Ladies, stay cautious! This mission is to test the new weapons—don’t get carried away!” Enterprise’s voice echoed across the waters.

”Understood!”

Zzzap!

The shipgirls slashed their way into the Siren fleet, beam sabers wreaking havoc among the smaller destroyers and frigates. Even the carriers and battleships sustained noticeable damage.

Just as the Siren fleet regrouped to counterattack:

”Retreat!!!”

With a burst of smoke from their destroyers, the shipgirls withdrew in an orderly fashion, disappearing beyond the horizon in moments.

The battlefield, left in ruins, was littered with shattered Siren wreckage.

Meanwhile, several shipgirls jotted notes into their notebooks:

”Experiment #1: MA-X200 beam saber. Medium manufacturing difficulty, low resource consumption.”

”Effective against Siren ships below cruiser class but struggles with battleships and high-ranking Sirens. Ayanami notes it’s inferior to her battleship blade.”

”Recommendation: Explore ways to enhance power output.”

”…”

Purifier sat dumbfounded on the sea’s surface, watching the shipgirls vanish like a whirlwind.

”What the heck was that?”

”Were they… experimenting on me?!”