Harry Potter : Reincarnated as The Greatest Wizard

He worked quickly, flipping through books and placing them into two piles: one for common books he didn't need and another for new, unfamiliar ones. Yulia, bound by her oath, couldn't withhold books outright, but Alex suspected she might try to disguise important ones as ordinary. That meant he had to check everything, no matter how mundane it seemed.

After a thorough sweep, Alex had divided the books into two groups. "Only about forty books I haven't seen before," he said, evaluating the unfamiliar pile. "Looks like the ones Yulia brought in from elsewhere aren't particularly high quality. I'll need to focus on the library itself."

Turning his attention to the bookshelves, Alex began pulling out books one by one, giving each a quick skim. Before long, he found something of interest. "Ancient Alchemy Minutes?" He retrieved a thick, heavy book from the top of a shelf. Its sheer size made it impossible to overlook.

Flipping through it, Alex found it was packed with ancient alchemical techniques, including numerous rune formulas that hadn't been optimized and some that had been entirely lost to history. "This is practically an alchemy history book." He smirked, setting the tome on the table. "Yulia, this one counts as only one book."

Yulia scowled from her spot on the sofa. "Can you hurry up? Are you planning to camp out here all day?" she snapped, clearly frustrated. The size of the book meant it couldn't be hidden, so she could only watch as Alex gleefully claimed it.

Ignoring her irritation, Alex continued his meticulous sorting, treating the process like a bargain hunt. He flipped through each book carefully, sometimes keeping them, sometimes returning them to the shelves. If this were a market stall, the owner would've kicked him out long ago.

Alex's sharp eyes caught sight of something interesting tucked into the bottom corner of a bookshelf. "Endless Darkness?"

The title alone intrigued him. The book's worn and unassuming appearance belied its ominous name, making him curious to dive into its contents. However, his heightened senses quickly picked up faint traces of magic emanating from the book. "Not so fast," Alex muttered, pulling out his wand. With a quick flick, he cast a general counter-spell to dispel any magical traps. To his surprise, the book reacted violently.

Bang!

The book sprang open with a sudden burst of force. Alex instinctively tossed it aside, but it was too late. He felt an unnatural tug at his senses as darkness enveloped him. His vision vanished entirely, and a thick, oppressive silence blanketed him. 

Reacting immediately, Alex pointed his wand into the void. "Lumos!" he commanded, but nothing happened. His surroundings remained pitch black, and the glow of the spell failed to pierce the darkness.

His brow furrowed as he analyzed the situation. "The wand feels normal. Magic power feedback is stable. The spell activated, but it's ineffective. That means…" He paused, his mind racing. "This isn't a spell failure. My senses are being tampered with directly."

Closing his eyes, Alex channeled his magic inward, focusing it on his mind. He visualized a surge of energy sweeping through his thoughts, scouring every corner of his consciousness. Occlumency, a skill he had honed to near perfection, was second nature to him now.

Moments later, he found the root of the problem: a foreign magical presence entangled with his thoughts. The magic was woven into runes he'd never seen before, disrupting his senses. Without hesitation, Alex directed his magic to flush out the intrusion. The process was slow but steady. Eventually, the runes unraveled, and the invasive magic dissipated. When he opened his eyes, the world returned to focus.

Yulia was standing nearby, watching him with a faint smirk that failed to hide her surprise. "Nice try," Alex said, brushing imaginary dust off his robe. "But it'll take more than that to trip me up. Though I must admit, the runes were fascinating. Care to explain why this book was left lying around?"

Yulia's expression faltered. She hadn't expected him to recover so quickly. Most people, even experienced wizards, would have been incapacitated for hours—if not permanently blinded. "Endless Darkness," she thought, her mind replaying a story she had heard long ago. 

Torquil, a renowned wizard, had fallen victim to the same book in his youth. It had left him blind for weeks, requiring the intervention of Old Travers to reverse the damage. The book had been sealed for decades, only recently resurfacing for this transaction. 'How did he undo it so fast?' Yulia wondered, biting her lip. Her plan to bait Alex into trouble had clearly failed.

Alex ignored her and turned his attention back to the book. "So, it activates on contact with magic. Clever." This time, he activated Occlumency before cautiously opening the book. The magic flared again, but his prepared defenses blocked the effects.

As the pages fluttered open, he scanned the contents with a mix of awe and intrigue. The book detailed a spell called Caligo Mentis, a form of dark magic that could instantly deprive a person of their sight and hearing by attacking their thoughts. The runes used in the spell were intricate, with subtle magical fluctuations that made detection nearly impossible. If left unchecked, the effects could cause permanent damage. "Impressive," Alex muttered. "This spell is dangerous, no doubt, but it's also ingenious. The thinking intrusion mechanism and rune concealment are remarkable."

A wry smile crept across his face as he added, "Of course, this little trap was meant for me, wasn't it?" He cast a sideways glance at Yulia, who quickly turned away, pretending to examine another shelf.

Realizing the value of the knowledge within, Alex pocketed the book and continued browsing the shelves. He remained on high alert, his Occlumency constantly active to prevent further surprises.

It didn't take long for him to notice something odd. Many books with ordinary titles had been swapped out with valuable texts. For instance, a plain-looking volume titled Theory of Magic contained advanced alchemical formulas, including the synthesis for Agrippa alloy—a rare and powerful magical material. "Looks like someone's been trying to hide the good stuff," Alex said with a smirk, flipping through another disguised book.

Yulia had a habit of hiding valuable books in the bottom or top corners of the bookshelf. Sometimes, she even tucked them among rows of books with nearly identical covers—a tactic Alex found both childish and amusing. However, nothing could escape Alex's meticulous search. Once a book passed through his hands, it was as good as found.

Sitting nearby, Yulia grew increasingly anxious. Every hidden treasure she had so carefully disguised was uncovered one by one by Alex. Her heart raced as he closed in on that particular book—the one she couldn't afford him to find.