“What do you mean, you’re going to narrow it down further?”

Rimle’s beard trembled slightly.

He sounded curious, but in truth, Rimle already understood what Ludger meant by those words.

He only asked to confirm it.

“You know what I mean, don’t you?”

“You’re telling me to modify my [Book Selection] magic?”

Rimle’s expression twisted fiercely.

Pointing out flaws in a spell to its original creator was considered an immense insult.

“So you’re implying my magic is still immature and requires improvement?”

“You could take it that way. But that’s not what I meant.”

“Oh? Then what exactly did you mean?”

“I’ll be the one narrowing it down. So, Sage, all you need to do is sit back and relax.”

“......”

At this point, Rimle found it so absurd that he didn’t even feel angry anymore.

But he still had to ask.

“You’ve only seen my [Book Selection] magic once.”

“Yes, that’s correct.”

“And you’re saying you’ll not only use it yourself, but you’ll even refine it? How is that any different from claiming you’re going to modify my magic at will?”

“It’s not modification. I’ll simply imitate the way you used it, but in my own way.”

“If that’s not modification, then what is it?!”

“Just imitation. Surely you’re not going to forbid me from even trying to copy it, are you?”

“Imitation? You’re saying ridiculous things! Do you think it’s that easy?”

[Book Selection] was a magic Rimle had developed by improving detection magic with his own unique method.

The principle, the procedure, and the results differed vastly from ordinary detection magic.

And this man claimed he could reproduce it after seeing it only once?

Even Loina, who acknowledged Ludger as a remarkable mage, couldn’t believe it.

But Ludger, with not a shred of doubt in his words, picked up a book and said:

“The detection magic you used was modified to respond to the letters written inside the book, wasn’t it?”

“That much is obvious just by looking. The important part is the method. Detection only tells you that an object exists; it doesn’t distinguish the contents of a book.”

“Right. So you altered the mana pattern to react only to a specific color. A book is, after all, white paper and black ink. If you make the mana respond to the darker color, you can analyze the letters.”

Of course, it wasn’t as easy as he made it sound.

You had to thread mana between the closed pages, which required extremely delicate control.

Yet Ludger placed his palm over a page and spread thin, wide mana across it.

The mana squirmed in response to the ink of the letters.

Seeing him actually do it, Rimle spoke calmly:

“Fine. Let’s say you can manage that. That alone is impressive. But my [Book Selection] magic isn’t something you can cast just by completing that step.”

“I know. The next step is to make the mana respond only to specific words, correct?”

“......”

“Since the mana reacts differently to each word’s shape, you just need to memorize the patterns of certain words and pay attention only to those. Of course, you’d need to layer detection magic twice for that.”

This time, Rimle couldn’t hide his reaction.

“...How did you know I used double-layered detection magic?”

“At first, I wasn’t sure. But when I tried it, one layer wasn’t enough. The structure is to reveal the specific word patterns with the first detection, then trigger a [signal] with the second.”

So Rimle’s [Book Selection] used two overlapping layers of detection magic.

And Ludger had figured that out after seeing it once.

For Rimle, this was the first time anyone had ever done such a thing. His expression was a mess of mixed emotions.

He tried to maintain his composure, but he couldn’t hide his astonishment—or even his growing admiration for Ludger.

He felt stubborn pride rising in his chest.

Fine. Let’s see just how much he can expose the core of my spell.

“And after that?”

“Since you used double-layered detection to send a signal, I’m guessing you marked certain word patterns in red if they appeared a specific number of times, and blue if they exceeded that number.”

“That’s right. It’s the clearest method.”

“Counting occurrences isn’t bad. But if you add a few more specific words, you’ll get even better distinction. Along with ‘Magic’ and ‘Mystery,’ you could add ‘Miracle,’ ‘Grace,’ and ‘Chosen.’ That will narrow it down even more.”

“And what meaning do those words even have?”

“Ancient mages believed that using magic was a blessing. They thought it wasn’t the result of effort, but a gift of grace, talent, and destiny. Naturally, their records reflect that.”

Ludger extended his finger, drawing out a thin thread of mana like a strand of silk and shot it at the books on the shelves.

The mana scanned the books rapidly, detecting countless words and arranging them into patterns.

Ludger analyzed the patterns, applied secondary filtering, and then the mana reacted, glowing faintly.

“Got it.”

He reeled the mana back through the thread.

His mana control was astounding.

“This way, you can find the desired books far more accurately. Of course, I can’t search as many at once as you can, Sage, but I can refine what you’ve already filtered. It’s all thanks to you.”

Ludger even gave Rimle credit, claiming his own method wouldn’t be efficient without Rimle’s help.

But Rimle barely heard it.

Wasn’t this basically him boning the fish, only for Ludger to swallow it whole?

It stung his pride terribly.

But he couldn’t say Ludger was wrong.

He had to admit it.

Ludger hadn’t just imitated [Book Selection]; he had improved it.

It was cleaner, more efficient.

And he’d deduced the spell’s mechanism after seeing it only once.

[Book Selection] wasn’t all Rimle had, but his pride still took a blow.

“You... You...!”

Finally, Rimle couldn’t hold it in.

“Fine, you’re amazing, you bastard!”

It was a childish outburst, but at its core was genuine acknowledgment.

In fact, it was practically a declaration of surrender.

If he wanted to be stubborn, he could still nitpick, but Rimle wasn’t that petty.

He admitted what needed to be admitted.

And Ludger had shown something that couldn’t be ignored.

“Damn, you use magic disgustingly well!”

“Thank you for the compliment.”

“You think that’s a compliment? Huh?! You really think so?!”

“A 6th-Circle mage said it, didn’t he? How could it not be a compliment? It’s practically high praise.”

“Wow...”

Loina couldn’t help but gape at Ludger’s brazen response.

Even his natural audacity was flawless.

And the fact that he wasn’t even trying to act like this made it shine even more.

“Let’s get started, then. We still have time before we leave the mansion, but time is money.”

Rimle filtered the books first with [Book Selection], and Ludger refined them in the second round.

That reduced the number of books to check significantly.

Arfa, Sempas, and Loina collected the chosen books and neatly stacked them in a corner of the study.

Only after circling the entire study once did they finish.

“How many?”

“One hundred thirty-two in total.”

“Still a lot.”

Even narrowing it down from tens of thousands to just over a hundred was impressive, but 132 was still a huge number.

And from here on, Ludger had to examine them alone.

Of course, Loina, Sempas, and Rimle didn’t stop working on their own analyses.

Thankfully, thanks to Ludger’s thesis from the Arcane Chamber, Loina’s progress was faster than expected.

‘This one’s useless.’

Pushing aside another book on modern magical theory, Ludger glanced at Loina, who had her head buried in a book.

“Are you all right, Miss Loina?”

“...Huh? You called me?”

“Yes.”

“Why?”

“Even though you came here with us, you do belong to an organization. Isn’t it a problem leaving your people behind like this?”

At that, Loina spoke casually:

“It’s fine. Those old men from the Alliance forced those people on me anyway.”

“So it wasn’t your choice?”

“The Mage Alliance might look like a single organization, but internally it’s split into countless factions. The ones who followed me are from different factions.”

“So they pretended to help you while subtly trying to benefit themselves.”

“Yes. So it’s actually much easier for me to work like this. Sure, I’ll probably get scolded when I go back, but I can endure that.”

“I see.”

Satisfied, Ludger refocused on the books.

He had already set aside ones worth noting, but nothing truly satisfying had come up yet.

Still, there were many books left.

He picked up the next one.

‘Hmm?’

This one wasn’t purely about magic.

It was a magical text, yes, but focused more on a different subject.

A holy war against demons.

‘Demons, huh...’

It wasn’t immediately useful, but curiosity made him turn the pages.

‘It’s explaining the existence of demons as commonly known, and how religion has fought them since ancient times.’

Normally, such accounts painted the church as righteous.

But this book was different.

It criticized the Lumenis Church.

‘The Lumenis Church back then was a symbol of absolute power, even holding the right to depose rulers. And yet someone dared to write this criticism?’

Intrigued, Ludger turned the page.

[Demons possess unique authorities. Their age doesn’t matter; their innate power alone allows a single demon to stand against an entire army. The Lumenis Church hunted their traces for ages, but not to uphold justice—only to protect its own authority.]

[The most famous battle was long ago, when a Saint led hundreds of Holy Knights against the Archdemon Suruna. The Archdemon, who had destroyed more than two small nations, perished along with Saint Arkenis in mutual destruction. After that, the demons, having lost their central figure, hid in the shadows of the world.]

‘A central figure?’

That differed from what Helia had told him.

Demons—those who called themselves Apostles—didn’t feel any camaraderie.

Yet this text referred to the Archdemon Suruna as a “central figure.”

Was the record wrong? Or had Helia concealed part of the truth?

Ludger kept reading.

[After the Archdemon’s death, the Lumenis grew arrogant and tyrannical. They meddled in other nations’ politics and often seized wealth under the guise of proving faith. They even took princes and princesses hostage. No one dared resist because they held divine authority—the horrifying power to manipulate human will.]

Ludger’s hand trembled slightly as he turned the page.

And then he realized.

This was no ordinary book.

He examined the cover, back, and foreword carefully.

The author left no name, no background.

Perhaps deliberately.

‘In case their identity was discovered...’

[That authority came from the Radiant God, Lumenis. Some rulers may not have believed in the god, but I know he exists—and he seeks to oppress us. The Lumenis Church is merely his tool, his puppet. We could not leave things as they were. Otherwise, we would live under oppression forever.]

[We found a way. We obtained a precious object that could end it all. But there was much to prepare. So we joined hands with the elves.]

[We built a massive facility and secretly nurtured a World Tree beneath it.]