Crossover Shipgirls: Building a Dimensional Empire from Scratch

Setsuna didn’t give Ainz much time to think.

To him, Cocytus was no different from a small roadside monster. He quickly began formulating the next phase of the operation.

”Everyone, follow the original plan and proceed to conquer the other nations in this world.”

”Conventional human weapons and magic won’t hurt you, but be cautious of World-Class Items and Divine Artifacts.”

He added a special reminder.

The Overlord world, being based on a game, featured some extremely powerful equipment due to its mechanics.

For example, the ”Downfall of Castle and Country” held by Black Scripture, known as one of the ”Twenty,” a world-class item with game-breaking power.

Whether these items would affect him, shipgirls, Heroic Spirits, or Spirits was currently unknown.

Setsuna had no intention of testing them with his own body.

Fortunately, before departure, he had thoroughly analyzed this world and had a fairly comprehensive understanding of the effects and holders of various World-Class Items.

Knowing both yourself and your enemy makes things easier to handle.

”Understood.”

The shipgirls of the expedition fleet began checking their assigned targets.

”Commander, Commander, what about me?”

”If you’re going to assault the Great Tomb, take me with you. I want to fight the Guardians. Cocytus being blown up in one shot was such a waste.”

”I even wanted to duel him with Barbatos.”

Gudako tugged at Setsuna’s sleeve, asking to join the mission.

”...I’ll think about it.”

Setsuna activated the sensors and began scanning for the location of the Great Tomb of Nazarick.

Naturally, the raid on the tomb would be conducted personally.

Commanding from above all the time was getting a bit dull; he was genuinely looking forward to a fight with Ainz.

According to the original plot, the Great Tomb was hidden underground and concealed with various cloaking spells.

Ordinary people and low-level mages couldn’t detect its existence at all.

However, it shouldn’t be able to escape the high-powered sensors aboard the Eternal Snowfall. Even if an exact holographic image couldn’t be obtained, the anomalous underground reactions would be enough to pinpoint its location.

...

The Great Underground Tomb of Nazarick, 10th Floor, Throne Room.

After witnessing the destructive power of the super-graviton cannon, Ainz was in a state of shock.

The opponent’s casual strike had power comparable to Super-Tier Magic—this was not an enemy that could be defeated by conventional means.

And there were over a hundred of those starships!

To fight them on the ground was simply courting death.

Even using flight magic, one couldn’t even get close to those space vessels.

”Ainz-sama, how should we deal with them?”

Shalltear asked with a confused look.

Having just witnessed one of the Guardians get one-shot, the others wore similarly complex expressions.

Facing such an unknown enemy, the Guardians had no choice but to rely on their Supreme Being to make a decision.

”...”

Ainz pondered for a moment.

”The enemy uses space warships. Fighting them outside puts us at a huge disadvantage. If we want to defeat them, we have to use other methods.”

”First, fortify Nazarick’s defenses. Then think of ways to ambush them, use teleportation and instant movement magic to assassinate crew members aboard the starships.”

He explained in plain terms to the Guardians what exactly a space warship was.

”You mean those things flying in the sky are controlled from within by people?”

Demiurge stroked his chin thoughtfully.

”Yes.”

Ainz nodded, giving the Guardians a crash course.

”A spaceship is essentially a human-made war machine. Though powerful, it requires humans to operate.”

”It’s like siege golems—once the operators are eliminated, the weapon itself becomes harmless.”

From his point of view, if they couldn’t defeat the starships head-on, then change tactics and take out the crew instead.

The result would be the same regardless.

Though Nazarick had never delved into technological research, Ainz didn’t mind creating a few spaceships himself.

”Oh!!!”

”So we just treat them as high-quality war machines?”

”I see! As expected of the Supreme One!”

The Guardians suddenly saw the light.

”Ainz-sama, may I boldly ask a question?”

Demiurge raised his hand.

”As you said, those starships are piloted by humans, but we don’t know the strength of the crew aboard them. How many of us should be dispatched?”

”Based on my judgment, the crew shouldn’t be too powerful.”

Ainz thought for a moment and reasoned it out.

”If their individual strength was truly high, they wouldn’t need to rely on space warships in the first place.”

”In human civilizations, spaceships are typically operated by engineers or technicians, equipped with only light weaponry at best.”

”They possess no special abilities, with combat power akin to ordinary humans or low-level adventurers.”

”We can teleport aboard using jump skills, seize control of the ship, and eliminate the crew.”

It was a reasonable assumption.

Since the vessels were technological constructs, they most likely originated from a tech-based world—just like Earth before he transmigrated.

Surely it wasn’t mages piloting the spaceships?

Against ordinary humans, Ainz believed they had a significant advantage. Modern firearms and similar weapons would hardly pose a threat to max-level Guardians.

”I see!!”

”The wisdom and insight of the Supreme One are truly beyond our reach.”

The Guardians felt enlightened, utterly convinced by Ainz’s reasoning.

”To be able to see through the enemy’s weakness so precisely in a disadvantaged situation, and to formulate the most suitable strategy to deliver a fatal blow...”

”This is the unparalleled brilliance of Ainz-sama!!”

Demiurge was filled with admiration.

He gave Ainz a deep bow:

”Forgive me, my lord. To think I required your guidance during a crisis to devise a counter-strategy. I am ashamed.”

”Ahem—”

Ainz cleared his throat, stopping Demiurge from over-imagining things.

”Ainz-sama, which spaceship should we target first?”

Albedo asked.

On the magical projection, various types of starships could be seen: carriers, battleships, cruisers, destroyers—large and small.

The Guardians couldn’t tell them apart.

”...”

Ainz pondered seriously for a moment, then pointed to the Eternal Snowfall.

Its massive hull and distinctive design made it stand out in the entire fleet.

”That one.”

”It’s the largest vessel, and it was at the front when descending into this world. The other ships flanked it—likely indicating it’s the flagship.”

”The enemy commander might be aboard it. Taking out the enemy leader would throw the rest of their fleet into chaos.”

A decapitation strike—a common tactic in PVP.

When someone invaded Nazarick, defeating the opposing team’s leader usually caused the rest to scatter.

Defeating that behemoth with conventional means seemed unlikely. Only through magic and pay-to-win items could a miracle be achieved.

”Then I shall lead a team immediately...”

Demiurge began but was interrupted by Ainz.

”Wait.”

He pulled out a strangely-shaped item.

”The enemy may have teleportation-blocking or displacement-prevention spells. Recklessly opening a teleport gate might alert them.”

”This is a World-Class Item. It allows mid-to-long-range teleportation unconditionally and is unaffected by defensive magic.”

As a pay-to-win veteran, Ainz possessed a large number of items and equipment.

World-Class Items were the top 200 most powerful items in YGGDRASIL, capable of breaking game balance.

Given the situation, the cautious Ainz decided to go all-in for the next move.

”It’s expensive, Demiurge. Use it wisely and make sure it succeeds on the first try.”

”As you command.”

Demiurge knelt on one knee and accepted the item.

”Shalltear, Mare, Aura, and the Pleiades, you’re going too. Bring along the Soul Eaters.”

Ainz selected several other Guardians as well as his battle maid squad.

He deployed some of Nazarick’s strongest forces, determined to strike the enemy with a surprise assault.

He didn’t believe anyone could withstand a joint attack from four Guardians and the Pleiades.

”With Ainz-sama’s strategy, there is no way we can fail. I shall carry out the mission with all my might!”

Demiurge gave another deep bow.

A few minutes later,

The four Guardians, together with the Pleiades, activated the teleportation item.

Shua—

After selecting the coordinates, a strange magic circle formed beneath their feet.

The World-Class Item’s effect was incredibly powerful.

With a flash of blinding light, they vanished from the spot.

...

Aboard the Eternal Snowfall.

Setsuna was scanning the Great Tomb’s location while assigning tasks to the various shipgirl fleets.

A group of Heroic Spirits, Spirits, and his oath-bound shipgirls were gathered around him, watching as he marked locations on the map.

”Bismarck, take the Iron Blood First Fleet to the Holy Kingdom and bring back the saintess...”

”Musashi, take the Sakura Empire First Fleet to the Slane Theocracy. Be cautious of Black Scripture and Antilene. Elma, why don’t you go with them?...”

”Royal Second Fleet, your target is the Baharuth Empire.”

Crack—

Suddenly, the sound of space fracturing echoed.

Alarms rang out across the ship.

As the Eternal Snowfall was part of his body, nothing inside it could escape Setsuna’s notice.

”Hmm?”

Setsuna abruptly looked up, sensing that someone had just used spatial magic inside his ship.

It wasn’t an ally. The power felt unfamiliar.

”Husband, we have intruders.”

The Spirit of Origin reached out, about to activate her domain.

”??”

”Wait, who wants to do a boarding raid? Let them through.”

Setsuna was intrigued. He wanted to see what was going on.

Shua—

With a flash of light, Shalltear, Demiurge, and the other four Guardians, along with the Pleiades and dozens of Soul Eaters, appeared on the bridge of the Eternal Snowfall.

They looked around at the starship’s interior, everything within completely foreign to them.

”Move. Exterminate everyone here. Capture the Commander alive if possible and bring him back to Ainz-sama.”

Demiurge had just given the order when he looked up.

There he saw Setsuna, surrounded by Spirits, Heroic Spirits, and shipgirls.

And it wasn’t a small group.

The Heroic Spirit squad, Spirit squad, and even several shipgirls had all gathered.

Each of them had different appearances and outfits, but none looked like the weak humans Demiurge had imagined.

A silver-haired girl, and two dragon girls with horns, exuding terrifying auras.

”...”

”...”

Both sides locked eyes and fell into an awkward silence for two seconds.

Clack clack clack—

The Royal Maids, led by Belfast, were the first to react. They stepped forward, shua shua shua, manifesting their riggings, gun barrels aimed directly.

The Heroic Spirits and Spirit squads, seeing the enemies, began transforming and summoning Noble Phantasms.

”Appear now! Zafkiel!”

”Astral Dress, Adonai Melek!”

”Luminosité Eternelle!!”

”La Grondement Du Haine!!!”

The bridge erupted in a kaleidoscope of magical lights.

Even before a real fight broke out, a barrage of field spells and strange Noble Phantasms forced the intruders into a scramble.

”???”

”Ainz-sama, this is not how the plan was supposed to go?!”

”The crew here seems way stronger than you said?!”

--------------------------------------------------------------------------------------------------------------

40 Advanced Chapters Available on Patreon:

Patreon.com/DaoOfHeaven