How to Use the Lord’s Future Diary

Chapter 5

Before the Great Cataclysm, in other words, before the Monster Apocalypse broke out.

This world was in a pseudo-medieval era of magical civilization.

It was very similar to the medieval era we knew, in that kings and lords had feudal contracts, but since mana, magic, and magical engineering existed, it was a much more convenient and prosperous world.

Thanks to the fact that magical items could also be used in daily life.

Of course, once the Apocalypse came, that too became a thing of the past.

‘And this place is still a land where people live. Where people exist, conflict follows.’

This land, where brilliant magical civilization had once bloomed.

Since it was still a place where people lived, conflict existed here as well.

Conflicts between lords, who had become rulers of their territories through feudal contracts, sometimes escalated into severe bloodshed.

When territorial conflicts burned hot, they even invaded each other’s lands through “Territory Wars.”

If war existed, then the development of weapons was also inevitable.

That “Mana Cannon” you see over there was a siege weapon created to inflict effective damage against fortress walls protected by reinforcement magic.

And the reason such a weapon was still neatly stored in our territory’s warehouse was thanks to the fact that, during the Apocalypse, our land was never invaded.

It seemed there was never really any use for it, so it had been preserved in its original state.

‘So there aren’t firearms, but things like that do exist?’

Unfortunately, in this world, firearms didn’t exist.

Whether it was because the materials for gunpowder didn’t exist, or because it had never been discovered or developed, I couldn’t know for sure. What was certain was that they didn’t exist at present.

And apparently, even before the Apocalypse, firearms had never existed.

From the perspective of preparing for defense, it was a shameful era, when machine guns or rifles were sorely missed.

I could already imagine our residents proudly mowing down monsters with a single rifle in hand.

Of course, given the nature of this world, it wasn’t like a single rifle could solve everything, but at least low to mid-level monsters could’ve been handled easily.

‘No matter how close I was to guns, making guns and gunpowder out of thin air would be impossible. But if something like that exists, maybe I could make meaningful use of it?’

“But hey, does that thing even fire?”

At my request, Peter, the master of the alchemy workshop, had hurriedly run over to the warehouse.

He squinted his eyes as he glanced at the Mana Cannon sitting in the corner.

It was as if to say, why did you drag me here just to spout nonsense?

“What? A Mana Cannon?”

“Forget the nagging. Does it work or not?”

“Well……”

“Well?”

“Ha, well, fine. First, let’s check it out.”

“Really?”

“After all, the era now and back then are different. Sure, it’s preserved in its original form, but whether it’ll actually function properly, I can’t say.”

Still, he gave a decent answer.

The Mana Cannon was a weapon that absorbed mana from the air and fired it in the form of a beam. Its power itself was quite decent, but since it was such an old relic, he said we needed to check first.

“Besides……”

“Besides?”

“That’s not really my field.”

It seemed Peter didn’t know much about that thing either.

Should I say their fields were different?

The alchemy workshop wasn’t a place that dealt with such mechanical devices.

If you compared it to modern times, maybe it was like the difference between a physicist and a chemist.

Still, I couldn’t just let it go, pretending not to know.

“Then take this opportunity to figure it out. I’m not asking for much—just make it so it can fire.”

“What, you’re telling an alchemist to tinker with a Mana Cannon?”

“Why not? You’re probably the only one in the whole territory who could even try.”

“Ha, you’re insane.”

In a situation where I couldn’t predict what kind of enemy might pop out and break through the walls—

The best course of action was to prepare anything we could use, no matter what it was.

‘And honestly, I am curious about a cannon that shoots beams like a laser.’

Wouldn’t any Korean man agree?

How could you resist a laser cannon?

If it didn’t exist, fine—but if it did, of course you’d want to fire it.

“Oh, right. By the way.”

“What now?”

“Couldn’t you make something explosive using mana?”

“What? An explosion? Not impossible, but……”

And another thought came to me.

Seeing that Mana Cannon, I wondered if maybe we could also create something else using mana.

Like a mana bomb or mana mines.

Everyone tends to think along those lines, right?

If monsters beyond what we could handle swarmed in, such explosives might be a huge help.

“I don’t think the effect would be that great though.”

“Really?”

“It’s possible. If you tune a mana crystal into an unstable state, it could explode even with a small shock. So it could be used as an explosive.”

“Sounds perfect.”

“But it’s not going to have that much destructive power. And besides, it’s basically the same as throwing money onto the ground.”

From ores mined in quarries, or from the hearts of monsters, one could extract “Mana Crystals.”

They were like universal batteries, used to power various magical items.

And yes, explosives could be made by using these mana crystals.

The problem was, their explosive power wasn’t that great, and more importantly—after the Great Cataclysm, mana crystals had been used as currency.

So in the end, it would literally be like using money as bombs.

“That is a bit much. Still, look into it anyway. Just in case.”

But I believed if there was even the slightest possibility, it was worth preparing.

The amount of mana crystals our territory had stored wasn’t that much, and each already had designated uses—but survival came first before anything else.

If my predictions were right, once countless monsters swarmed toward the territory, we could replenish spent mana crystals by harvesting new ones from their corpses.

“Hey, do you even hear yourself?”

“Why? What’s the problem?”

“You know damn well how busy I am right now, don’t you?”

“You are busy, sure.”

“And then you asked me to fix that Mana Cannon.”

“I did. So go do it.”

“And now you’re asking me to make bombs out of mana crystals?”

“Hmm, but shouldn’t you still do it?”

“What the hell…….”

After piling up so much work on him, Peter seemed just thrilled.

What else could I do? No matter how busy he was, some things had to be done.

Because in our territory, he was the only one capable of handling such matters.

Even if he complained like that, he was capable enough that I believed he would somehow manage it.

‘Alright, then I guess I’ll just wait and see?’

For some reason, I had a feeling that cannon would end up doing something amazing.

---

The expedition had been temporarily postponed, but the territory was bustling with activity.

The residents were all busy making shields for themselves.

Near the “Forest of Illusions,” forbidden to the southwest of the territory, they were cutting down sturdy Ironwood and reinforcing it with leftover monster hides from the territory to craft shields that were at least somewhat usable.

“So, how’s the Forest of Illusions side?”

“No particular problems. As long as we don’t venture deep into the forest, it’s not especially dangerous.”

“Don’t lower your guard. Report immediately even if you notice the smallest sign.”

The “Ironwood Task Force” included many of the territory’s knights, soldiers, and rangers.

If, while logging at the edge of the Forest of Illusions, they encountered monsters too strong to handle, even the bravest residents could suffer casualties.

And through this Ironwood Task Force, I was also keeping an eye on the movements within the Forest of Illusions.

‘If monsters do swarm in from the south, the problem is most likely coming from the Forest of Illusions. Something like that couldn’t break out without signs beforehand.’

The chance that monsters from the Monster Mountains ignored our planned expedition and instead struck directly at the territory was extremely low.

And I also found it hard to imagine that wandering packs of monsters could inflict truly fatal damage to the territory.

So in the end, if trouble did arise, it was most likely from the Forest of Illusions—and to detect such signs, regular scouting was essential.

Even after the Ironwood Task Force finished logging, I intended to keep the forest under close surveillance, so that we could immediately catch any signs of change.

‘Still, our residents really are something else.’

But there was something a bit absurd about this situation too.

To make shields, they had no choice but to set aside their farm work for now.

Securing Ironwood, processing it, and then crafting shields required a lot of manpower—especially since the number of shields we needed to produce was no small matter.

It was spring now, a time when the farmland required plenty of work, so naturally, asking them to stop farming would normally spark complaints.

But not a single resident voiced dissatisfaction. They simply focused on making shields.

From the looks of it, they actually seemed to enjoy crafting shields far more than working in the fields.

From hunting to gathering, to crafting—they were capable of many things, but farming seemed to be the one thing they truly disliked.

‘The only one who raised an issue was the Steward. And even then, it wasn’t exactly a complaint—more like concern.’

Steward Harold, who oversaw internal affairs of the territory, expressed worry about this decision that practically abandoned farming.

He feared the worsening of food supply conditions.

But when I told him I had a plan, he cautiously held his tongue.

‘If monsters swarm in, farming will be ruined anyway, so we’ve given it up for now.’

The fact that no complaints had surfaced even in this situation showed just how strong the lord’s authority was within the territory.

Even though I had recently squandered most of the surplus funds of the territory through a marriage scam and a failed mining development, the situation was still like this.

As long as we could somehow maintain the territory, it seemed the people didn’t need to worry about survival.

When I had suddenly transmigrated here, I’d worried about what I should do, but now it felt like the path was slowly coming into view.

“Damn, this is needlessly complicated.”

“So? Think you can do it?”

“Who do you think I am? I managed to make it work somehow.”

“Oh, really?”

And right around then—

After days of struggling with the Mana Cannon, Peter finally brought good news.

He had somehow tuned it to the point where it could actually fire.

But, of course, it wasn’t without problems.

“I don’t think we can even test fire it.”

“Why not?”

“Because once we shoot it, that’ll be the end of it. It’s not just that it’s old—the concentration of mana is different now. This was made based on pre-Cataclysm standards.”

“Ah, I see what you mean.”

When dimensional rifts opened, the density of mana had multiplied several times.

Even while suffering enormous losses from monster attacks, humanity had somehow endured, largely because knights grew stronger day by day.

For example, before the Great Cataclysm, there had been only a single “Master” in the entire kingdom. Now, just in the southern Ribella Peninsula alone, there were about ten.

In such circumstances, it was no wonder a weapon designed to absorb mana from the air and fire it couldn’t function normally anymore.

“So basically, it gets overcharged. It draws in too much mana and overloads.”

“Exactly. It’s not a device built for delicate control, so it can’t be helped.”

I thought I’d stumbled upon something impressive, but it turned out to be a one-use glass cannon.

The fact that it could only be used once was undeniably disappointing.

Still, there was one positive aspect—its raw power had increased compared to before.

“Don’t get your hopes up though. Who’s going to just sit still and take the hit? Any knight with a bit of skill could dodge after seeing it. There’s a reason it was only used for sieges. And against high-rank monsters? Forget it.”

“I see. Nothing’s ever easy, huh.”

“Come on. If it was really that useful, don’t you think they’d have been using it ages ago?”

So it wasn’t really some laser cannon that fired at the speed of light.

That was a bit disappointing.

If even knights could dodge it, then it was far weaker than what I’d been hoping for.

Still, since the destructive power itself was real, the only choice was to consider situational ways to use it.

“And what about the mana crystal bombs?”

“Those are ready too. Honestly, I think you’re insane.”

“Ah, well. Fine. The point is, they’re prepared, right?”

Diligent Peter had even prepared the mana crystal bombs I’d asked for.

I guess engineers really did shine brightest when pushed to work.

Ironwood shields, the Mana Cannon, and mana crystal bombs.

Individually, they were somewhat lacking, but together they definitely gave a sense of being prepared.

And around that time—ominous signs began drifting in from the Forest of Illusions to the southwest of the territory.