Swish——
With the opening of the temporal passage.
Lu Chen and his group returned to their world.
Blue sky and blue sea, gentle breeze blowing.
The undeveloped Earth, just the air quality was several levels better than the Demon Slayer world.
They were in the early stages of the Industrial Age, with no environmental awareness at all, PM2.5 was probably off the charts.
"We've been gone for over a month, I wonder how everyone is doing?"
"How is Yixian managing things here? She should be fine, there's no one who would come to attack us anyway…"
Lu Chen was thinking that.
"Hi~ Commander, you're back!"
Suddenly, a childish greeting came from above.
Looking up, a small silver-haired, beast-eared ship girl was floating in the air like a rocket soldier.
She had a large jetpack on her back, suspended about a few dozen meters above the sea level under the effect of plasma jets.
"Yukikaze?!"
"How did you start flying?!"
The five ship girls accompanying them looked up in amazement.
"Didn't Commander give Ming Shi and the port area a lot of technological data from the Gundam world? When we were building Gundams, we also took the opportunity to study the technology in it."
"Some of it wasn't useful, but the Gundam's aerospace propulsion system, energy weapons, etc., were quite interesting."
"While you were in the Demon Slayer world, we were bored and just improved our equipment, it was fun, nanoda!"
Yukikaze adjusted her jetpack and landed in front of them.
“……”
Lu Chen remembered that after he sent the technology to the port area, the Azure world was frantically experimenting with weapons and constantly bothering Big Eye Moe.
They installed Gundam's propulsion system on themselves, wanting to achieve aerospace maneuverability like planes.
However, the first propulsion system they built was a bit of a performance art, it could only fly a dozen meters, and many ship girls even crashed, falling into the sea in a state of confusion.
This improved version is much more advanced, not only smaller in size, but also with greater thrust, able to launch the several thousand tons of destroyers into the air with their expanded ship gear.
"So you can all fly now?"
Richelieu asked in disbelief.
"No, only destroyers can, you big sisters can't, you're too heavy!"
Yukikaze put her hands on her hips, a proud look on her face.
She started her jetpack again, swooshing up into the sky, drawing a cat's head with her tail flames.
This was the first time she was proud of being light because of her tonnage, she used to be the one who envied the combat capabilities of cruisers and battleships.
Lu Chen looked at the sea in the distance.
There were still many destroyer ship girls wearing jetpacks, flying around in the sky above the sea.
They can also manifest their ship gear in the air, carry out naval gun strikes on the ground, they are very flexible and maneuverable, capable of sea, land and air three-pronged combat.
Battleships and aircraft carrier ship girls below cast envious glances.
“……”
It has to be said that developed military industry has its benefits, the Gundam technology they obtained not long ago has already begun to combine the characteristic technologies from it with the ship girls of the Azure world.
The direction of development was a bit beyond Lu Chen's expectations.
"This is the Rocket Soldier Pro Max Edition, the ship girl fighter?"
"Why does it have such a strong flavor of Azure Lane spies stealing the combat laboratory of the Gundam world..."
……
After the little interlude.
The ship girls quickly noticed the returning expeditionary force, welcoming them with a feast, inquiring about their well-being.
The small ship girls who couldn't join the expedition surrounded them, dragging them to talk about the Demon Slayer world.
From Richelieu blasting Douma into ashes with one shot, to air raids against Muzan's army, the Black Ship Incident opening up the country, conquering the entire world.
It made the other ship girls blood boil.
"Wow, you had all the fun without me!! Commander, I'm going next time!!!"
"That Royal Navy fleet, I can beat them all by myself!!!"
A few small ship girls protested loudly.
Lu Chen soothed them one by one, promising to take them out to play next time.
"So, now, let's do a combat summary."
The vanguard fleet gathered among the commanders.
Every combat operation of the ship girls needs to be summarized, including the consumption of resources, the harvest, whether the strategic objectives were achieved, and so on.
The expedition was no exception.
"The technological level there is not high, there is nothing of value in terms of magic or transcendent power."
"One book of Breathing Techniques, one book of Blood Demon Art, those should be the strongest things there, oh, and there's a vial of Muzan's blood, let Ming Shi take it to study."
Lu Chen placed the two books and a vial of the blood of the ancestor of demons on the table.
Yukikaze curiously flipped through a few pages of the Breathing Techniques.
"Breathing Techniques? And swordsmanship?"
"Can I learn it?"
“……”
"You can if you want, but I don't think it's necessary?"
Lu Chen chuckled.
"This thing is for enhancing human physical fitness, no matter how hard you train, you can't turn yourself into a battleship?"
"You're under engineering, it's better to get a larger, sturdier hull than practicing."
The encyclopedia clearly states that ship girls are technological creations, their combat power is mainly improved through technological advancements in engineering and physics.
"Hmph, who wants to change their hull to a battleship, they can't fly anyway."
Yukikaze pouted.
"Besides, our biggest gain is the complete conquest of that world."
"From now on, the Demon Slayer world will serve as our material production site, providing resources for the port area and here."
Lu Chen placed several diplomatic documents on the table, all signed with the countries over there.
"The way you told it, it feels…a bit violent?"
Ning Hai tilted her head and thought for a moment.
"I'd like to cooperate peacefully with them, but the problem is, there's not even a world government there, even if I wanted to support a proxy, I can't go and look for the Qing Dynasty, can I?"
Lu Chen laughed.
"I can't talk to those capitalists either, they all have a thousand eyes, they love to scheme against each other."
"So it's better to cut the Gordian knot, just knock them all down."
He wasn't a war maniac, but the world in the early 20th century was chaotic.
Military conquest is the fastest and most effective method, break it down and then rebuild it, and then establish a new order.
"So we just have to wait for them to pay tribute on time? Send someone over every few months to collect the resources?"
Ping Hai asked in a daze.
"Yep, but there are other things we need to do before that."
"We're going to do sustainable overfishing, first it needs to be sustainable, then we can overfish."