"What's the real reason for this trip?"

Zelretch raised an eyebrow at his pupil.

"You are overthinking things again. No, this is not a test, or anything like that. I suppose I am simply in a charitable mood today." The old man's smile slowed turned into a grin, on that was jagged and sharp, the kind used to tear flesh.

"But if you really require a reason for this errand, then we are here to celebrate the death of a certain person."

Kazuma only hummed in acknowledgement.

"Who was it? Sealing Designates are beneath your notice, no magus in their right mind would challenge you to a duel…"

"Well, Prelati's not very sane, so he's an exception. The brat's tenacious though; Aozaki's going to have to kill him a few more times for him to learn his lesson and sets up that Grail War in Snowfield."

Soon, Ahenenerbe came into view. The interdimensional café sported their poorly chosen name on a sign hanging above the entrance, which the two spared only a momentary glance at before entering the establishment. Despite it being noon, there was a noticeable dearth of customers, with only a girl wearing a red jacket outside her kimono and a red haired boy before them. It was also darker than what Kazuma expected. The sole sources of light came from the entrance and four windows placed on either side of the shop; the sunlight flowing in and silhouetting the tables and customers in dark, hard-cut outlines. The tables further inside the shop aren't so lucky, and projected a more solemn air with their gloom. It painted a nostalgic picture, as if some tavern had stepped out of antiquity into the modern age.

The two magicians sipped the tea they had ordered.

"Do you prefer tea or coffee?"

"Since we're drinking tea, shouldn't it be evident?"

"Just answer the question. Both? None? A mixture?"

"Who mixes coffee and tea?! And I prefer tea."

"Good. You just won me a favour from an old friend."

"And here I thought you weren't a betting man."

"It's important to enjoy the small things in life."

The spontaneous conversation died out the same way it began. Spontaneously, in case you didn't know.

"Say Boss, why exactly did you name the shop after a Nazi operation? I get that your German and all, but isn't this a bit much?~"

Magical Emerald jumped out from beneath Zelretch's cloak and bounced around the table like a grade schooler experiencing their first sugar high.

"Well, I just chose the name at random. Changing it is too troublesome."

"Too troublesome? Finally starting to sound your age then - ack!" In a movement too fast to be human, the old mage clamped a vampirically strong hand around the Kaleidostick's handle.

[Deactivate]

The wand went limp in his hands.

"I still don't understand why Kaleidosticks even exist. The Jewelled Sword is more than an adequate substitute, even if it lacks autonomy."

"Well, I wanted to test a hypothesis that all Magics are reflections of themselves. The Blue can emulate some of the time altering effects of the Kaleidoscope, while the Third Magic is capable of extremely limited dimensional travel. They overlap at certain points, you see? To test this, I attempted to replicate the effects of Heaven's Feel with the Second Magic. That's how the class cards were developed.

That wasn't quite successful. I got bored and moved on to see if I could grasp the ability to manifest Noble Phantasms in the Local Worldline."

"I see, so that's how the initial concept of the Kaleidosticks was developed. Inorganic familiars designed to operate in simpatico with Class Cards to produce manifest Noble Phantasms."

"Long story short, I got a bit too enthusiastic and, via a set of alchemical reactions, gave them sapience. After that, I went all the way through and modified them into the forms of totems magical girls would use. I thought it would be funny at that time."

'Of course you did...'

"That was what I intended with Sapphire and Ruby. Emerald, on the other hand, I made specifically to act as an anchor, compass and regulator during resonance. Streamlines the whole process and acts as a safe guard."

The sword swung down.

Reality was broken as what was impossible was made possible.

Three attacks performed simultaneously. Not at ridiculous speeds, but truly at the same period in time. Three attacks that, when used together, provided no escape.

Stop!

His concentration was broken, and instead of being killed, the man before him received two cuts that would bleed hard, but weren't fatal, while the third missed entirely.

Mitsurugi blindly lashed out, flailing with no direction. Finish him, a slice to the neck, gouge out his eyes- no, this is all wrongSHUT UP.

The wave of thoughts surged, threatening to split his head open, then slowly, mercifully receded.

Mitsurugi's followers had drawn their weapons, while Darkness had gotten in front of him, sword drawn.

So... are you supposed to be a hidden protagonist power or something? Please shut up for a moment.

Moving his counterpart's body into a standing position, Kazuma held up his hands.

"Look, this is all just a misunderstanding."

"This is all just a misunderstanding!"

"Then you'd better start talking sense, 'Emerald'. What. Happened. To. Kazuma."

"Well, he's just stuck for a bit-"

"Emergency broadcast! Emergency broadcast! Attention all adventurers, please prepare all your equipment and gather at the town's main gate. Especially Satou Kazuma-san and his companions, please head to the scene as soon as possible!"

As if on cue, the ground started rumbling ominously.

Flinging Kazuma's unconscious body over her shoulders, Darkness walked outside.

"Darkness, where are you going? Don't tell me you want to fight the mobile fortress destroyer? Taking on that thing without Kazuma would be reckless."

"Well, it wouldn't hurt to try." Aqua shrugged nonchalantly.

Megumin turned to her with an incredulous look.

"Think about what you just said! Not even an explosion can get past its magic barrier! Do you really want to risk your life fighting something like that?"

A staff appeared in Aqua's hands.

"Well, this one has grown attached to this town with its Egil trees and giant toads. It would be a shame to see it reduced to dust and rubble."

She then attempted to strike a heroic pose.

"Once we defeat the mobile fortress, the entire country will know our names. Soon, the Axis Church will spread and crush the black hearted Eris worsh-"

"I should have expected something like that." The arch-mage sighed. "And you, Darkness?"

"A crusader must never forsake the people they are responsible for protecting."

"Yep. Thought so."

"Oh, you came! Though I don't understand why Kazuma is unconscious or why there is a green wand stuck to his face..." Luna's enthusiastic greeting slumped into confused muttering.

"Magecraft accident."

The assembled adventurers began to talk amongst themselves.

"Thank you for responding to the emergency broadcast today! We will now start the emergency quest to repel the destroyer. There are no levels or job restriction, we hope everyone will take part. When the guild judges the quest to be a failure, we will abandon the entire town and all escape together. All of you here are the last line of defence for the town. We are counting on you!"

The staff announced with a loud voice, lowering the chatter down to a tense silence.

After that, the staff pushed the tables in the bar section into the middle of the guild, setting up space for a temporary conference room.

"Well then, everyone, we will start the emergency war council. Please take a seat!"

"Alright, I will brief the current situation! Erm… First, is there anyone who needs me to start by explaining what the mobile fortress destroyer is?"

Several adventurers raised their hands.

The staff nodded in acknowledgement and began:

"The mobile fortress destroyer is a gigantic golem, built by the nation Leidengard, which has advanced magic technology to wage war against the monster nations around it. Using their national budget and depleting their vaults, they constructed a colossal spider-shaped golem, the size of a castle. Utilizing large quantities of enchanted metals, it is far lighter than it looks, able to move faster than any horse."

The sound of plates clinking against each other.

"Worth mentioning is its enormous body and attack speed. Even a large sized monster would be turned into mush if struck by one of its limbs. The torso is protected by a magic barrier which could withstand any spell, up to explosion magic, as demonstrated in the 34th assault."

The sound of morale falling could almost be heard. The chairs and tables have began to audibly shake.

"Magic is ineffective, so we can only attack physically. We will be squashed if we go near. So we only have ranged attack in the form of arrows and catapults left. But the golem's defences are formidable to the point where arrows would just bounce off; as for the siege catapult, it would be hard to use it with the speed of the mobile fortress. To guard against aerial attack from monsters, cannons are situated on the body of the destroyer."

"..."

"The fortress went out of control during the destruction of Leidengard. With its incredible speed, there are no places on this continent which hadn't been ravaged by it at least once. As it does not discriminate between men or monsters, the rampaging mobile fortress is known as the destroyer. Whenever the destroyer draws near, the handling method endorsed by the guild is to abandon the town, wait for the destroyer to pass through, and rebuild the town. It is being treated as a natural catastrophe."

"Right now, the destroyer is towards the northwest of this town, heading straight for us. Since Kazuma-san is incapacitated and will not be able to participate, teleporting the entire town to a safe place won't work, so everyone, please give your suggestions!"

An adventurer tentatively raised a hand. "There might be plans of the destroyer left in the ruins of Leidengard..."

"No one was able to make any headway into the ruins without been attacked by those spider monsters. Any other suggestions?"

And so, another adventurer raised his hand:

"To deal with that thing, we need to dig a giant trap near the town…"

"It has been attempted before. Elrich gathered a lot of 'elemental masters', summoning the spirits of the earth to dig a big hole, and the destroyer fell in successfully. Everything was going as planned until the destroyer simply jumped out. Their plan included throwing down boulders to seal the hole, but they couldn't execute that in time."

"…"

The place fell into silence once more.

"… Any other ideas?"

Unexpectedly, it was the delinquent adventurer Dust who provided the next suggestion. "Well, the main problem is the destroyer's barrier and high mobility. If we get that Axis priestess to flood the area, then the destroyer's weight would pull it into the mud and slow it down. Unfortunately, we still have to deal with the barrier."

Laughing, Aqua stood up. "Leave the barrier to me, for I will shatter it in a single attack!"

If it were anyone else who made such an outrageous claim, Darkness would have thought that they were touched in the head. But this was Aqua, who despite her delusions of being a goddess, was capable of casual resurrections.

"There is a way to break the barrier?! The destroyer's barrier?"

Megumin waved her hand hurriedly.

"No, she said there is no guarantee."

"What nonsense are you spewing? You think my spell break cannot shatter a barrier? The only one who gets to decide such things is me!"

Spurred on by Aqua's boasts, the entire hall turned rowdy.

"Anyway, could you please give it a try? If it works, we can attack with magic…! Ah, but low level spells are useless against that mobile fortress. All the adventurers in this town are novices, our mages are lacking in firepower…"

The staff became troubled again and the place fell silent once more.

At this moment, a certain adventurer pointed out:

"Don't we have someone with amazing firepower? The one with a screw loose."

Once he said that, the guild became loud again.

"That's right, the explosion maniac!"

"Wait, there's also that loner girl! The screwed up one!"

Yunyun sighed in her seat at the back while Megumin stood up in anger!

"S-Shut up!"

She started blushing in everyone's gaze of anticipation.

"Ughh… Even with my explosion spell, I might not be able to… finish it off in one shot…"

She mumbled this and sat down immediately.

Slam!

"Sorry I am late! "

The one barging into the guild was Wiz who was wearing an apron on top of her black robes, who seemed to be in the middle of work.

From her dressing, she looked like a girl that came to help in the distribution of emergency food rations.

When the adventurers saw Wiz…

"It's the owner of Magic SHop Reon! !"

"The Ice Witch is here!"

"Shop owner, thank you for taking care of me in my dreams!"

"We will win! We will definitely win!"

The cheering started instantly.

"Why is that shopkeeper so famous? "

"Don't you know? Wiz was originally a famous wizard. She was a renowned archmage, disappearing for some time after retirement before showing up in this town suddenly to set up shop. Her business isn't good because most of the adventurers in this town are novices, and can't afford the expensive magic equipment in her shop. It would have been better if her shop was in the capital. We don't need to fight powerful enemies, so we have no use for pricey potions and magic items. Everyone drops by the shop just to see the beautiful shop owner, but don't buy anything."

While ushered by the staff, Wiz nodded at the people around her, sitting at a table somewhere in the middle. Soon, a workable strategy began to develop.

It was like putting sugar cubes into a glass of water. Emotions and memories that were both his own and not flowed and mingled with his own then settled down as he adjusted to the change.

Kazuma continued to draw the magic circle. After determining which Worldline he was in, all he had to do now was find's Emerald's connection and trace that back to his own world. In theory.

Unlimited mana? That's so broken! And taking things from parallel worlds? Why didn't you just get enough money to hire adventurers to take down the demon king for you?

The demon king of my world is allied with someone just as hax as I am, so you can see why that wouldn't work.

Aside from the adventurers, the townsfolk were gathered in front of the town, working nonstop to construct a temporary barricade. The designated area to intercept the destroyer was the plains before the main gate of the town. They knew it was useless, but the adventurers with the relevant jobs still set up simple traps. In front of the barricade, a group of alchemists congregated in heated debate as they drew formulas on the ground.

"Hey Darkness. I am telling you this for your own good, so retreat for now. I know how tough your defence is, but you are pushing this too far. Just let go of your useless fetish and wait at the side of the road with me, alright?"

"Chris, you know why I can't leave. A crusader's duty is to protect the citizens of this town; besides no one else is more suited for my role."

"You want to feel the pain of been beaten up by a fortress sized golem?"

"Of course. The more I suffer, the less everyone else has to."

"You are really stubborn sometimes."

...

The rumbling had grown louder, and the ground shook.

"Are you nervous? "

Yunyun strode up to Megumin, who was standing by at the side of the Destroyer intercept zone.

"Ha! O-Of course not! I will definitely succeed..."

"Yeah, I'm a little scared myself."

"Attention all adventurers, the mobile fortress destroyer is about to appear before us. Citizens, please evacuate out of the town! Adventurers, please get ready for battle!"

From behind a cluster of hills, it emerged.

A metallic colossus in the shape of a spider, scuttled on building-sized legs, each step crushing the earth beneath it. Countless barrels of weapons lined its sides. Worse, it moved at a blindingly fast speed, much much too fast for something so gargantuan. A weapon made to obliterate entire armies, endure salvos of high-level magecraft and prevail.

[HOSTILE ENTITIES DETECTED]

The Destroyer halted for a brief moment, before turning towards the town.

[ACTIVATING ETHERCANNONS]

.

.

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AN: Sorry about my long absence, but I had a rather severe case of writer's block. I planned everything out already, but it was just so frustrating to write it down.

Tsubame Gaeshi is a technique where three concurrent arching blades close on the enemy from all sides to create a prison, allowing no chance for defense or evasion. While he downplays it as simply successive slashes done "quickly", it is actually bending the laws of physics to multiply its existence. It starts with a flash from this world, followed by two absolutely simultaneous, over-lapping flashes that disregard the concept of time and space, producing a slash attack that arrives from three different directions by momentarily using the Multi-Dimensional Refraction Phenomenon of Zelretch's Second Magic to transcend speed, dexterity, feints, and many other elements.