Harry Potter : Reincarnated as The Greatest Wizard

Charles tried to maintain his stance under Alex's sharp gaze. Within just two minutes, his arms began to ache and shake, making it almost impossible to stay steady. Frustrated, he grumbled under his breath, but his complaints died in his throat when he noticed Alex holding the same position effortlessly, not even breaking a sweat. Left with no excuse, Charles clenched his teeth and pushed through.

Finally, after what felt like forever, Alex allowed him to stand up. Charles's legs and arms were stiff and trembling as he staggered toward the hut. "Do you do this kind of thing often? Are you even human?" he muttered, still panting.

Alex smirked. "It's tough at first, but if you stick with it, you'll see the results. This is just the warm-up. Starting tomorrow, we'll add a minute each day until you can hold it for ten minutes straight. After that, we'll work in magic training, followed by stepping drills, and then combat exercises."

Charles groaned, his mind spinning at the thought of the escalating difficulty. Meanwhile, Alex recalled the words of his old instructor: "The finest steel is forged in the hottest fire." It was a principle he now intended to apply to Charles's training.

By the time they finished for the day, Charles was practically dragging his feet back to Gryffindor Tower, where he collapsed onto his bed without even bothering to change out of his clothes.

The next day, Alex carefully monitored Charles's progress. Despite his initial struggles, Charles was starting to show improvement. His endurance was better, and his growing sensitivity to magic allowed him to cast spells with more precision and power. Even the more challenging spells were becoming easier for him to handle.

At the same time, Alex was diving deeper into his research with Professor Bones. The professor had him working on a thesis about the Echo Spell and introduced him to practical alchemy. These alchemical spells were subtle, requiring no verbal incantations and being used primarily on enchanted objects. The applications ranged from speed and strength enhancements to silencing effects and pressure resistance. Alex felt his progress was steady and satisfying.

About a week later, Charles brought some news. "Hey, there's a senior named Granda Chitoc who just got back to Hogwarts. I convinced him to teach us the Waves Repelling Charm—though I had to promise you'd give him a poker set as thanks."

Alex chuckled. His casual poker games had apparently earned him a reputation across the different houses. "Well, if it gets us the charm, I guess it's worth it."

Excited to test the spell, Alex set up a large basin and filled it with water using the Clear Spring Charm. He tossed a stone into the basin, creating ripples, and then cast the Waves Repelling Charm. The incantation was long, suggesting the spell was still a work in progress, but it worked. The waves immediately settled, leaving the water still.

Encouraged, Alex tried it on sound waves next. He used an Echo Spell and tested the charm while wearing his monocle. The results were decent; the charm softened sound waves, but not as much as he'd hoped.

"Hm, just as I thought. It works, but it's not strong enough," he muttered. "I'll need to tweak the runes to make it more effective."

Deciphering a spell's runes was no small task, especially when it involved reverse-engineering the entire structure. Luckily, this particular spell was still unrefined, making the process a bit more manageable. With two intense days of work alongside Professor Bones, Alex finally cracked the spell's rune configuration.

"So, it combines the 'repel' rune with 'eliminate' and 'stabilize.' That explains why it calms waves. If I add a rune to detect sound waves specifically, it could block noise more effectively," Alex mused as he sketched out his ideas. Energized by the potential, he began designing improvements.

Over the next several days, Alex poured himself into refining the spell. Drawing on his experience from creating two other spells, he encountered fewer obstacles and quickly developed four new rune combinations based on the original setup. By the end of October, the spell was ready for testing.

Alex divided his testing into two phases. First, he checked to ensure the spell wouldn't harm living creatures. He cast it repeatedly on a lab rat, watching closely for any signs of distress. Once he confirmed it was safe, he moved on to phase two: testing the spell in real-world scenarios. He called his creation the "Sonic Repelling Spell."

To test its sound-dampening properties, Alex cast it on himself. As he amplified the spell's power, he gradually tuned out the surrounding noise until even Hagrid's distant shout became silent. Satisfied with its success, Alex tested additional applications, including an Echo Spell and even an Infrasonic Spell.

Of the four rune setups he'd devised, Alex concluded that the third was the most effective, particularly for blocking ultrasonic waves. "This will be the foundation for further upgrades," he decided. Though tempted to test the infrasonic version on himself, he held off, wary of potential side effects.

Finally, on Halloween night, Alex was ready for the ultimate test. Preparing thoroughly, he brought healing potions and asked Hagrid to keep an eye on him from a safe distance. At exactly 7:19 p.m., he recorded in his journal: "Second test of the infrasonic spell."

With the Sonic Repelling Spell active to shield his ears, Alex cast the infrasonic spell. At first, he felt nothing—no sound, no vibrations—until he glanced at the lab rat and froze. The creature lay motionless, blood trickling from its ears and nose.

"It worked," Alex murmured, both awed and disturbed by the spell's lethal power.

As he prepared to test its range, Hagrid suddenly came running toward him, waving urgently. Realizing he still had the Sonic Repelling Spell active, Alex quickly dispelled it.

"What's going on, Hagrid? I couldn't hear you," Alex asked.

Hagrid looked flustered. "Dumbledore needs me. Just wanted to check you were alright before I left."

With that, Hagrid hurried off toward the castle, leaving Alex alone to reflect on the power—and responsibility—of his new creation.