—No, calling it "perfectly restored" wasn't accurate.
In fact, the reattached arm looked rather crude.
Lewis clearly noticed that the arm was slightly crooked—the skin at the joint didn't align properly—and it had even grown a bit longer, making the two arms uneven in length and extremely awkward in appearance.
But that was the most terrifying part.
Even with such a rough reattachment, the troll had still managed to reconnect its severed limb—and could use it as if nothing had happened.
This meant the troll was relying entirely on its absurd regenerative ability.
But how was that possible?
There had never been any mention of trolls in the Harry Potter world possessing such regeneration!
What exactly was going on?
Lewis's mind raced.
The vast database of magical knowledge he had accumulated offered no answers.
Instead, it was his memories from his previous life that gave him a clue.
"This troll… could it have merged with traits from trolls of other worlds?"
The realization struck him instantly.
Of course.
If beings like Ciri from the wizarding world could appear here, if drowners could exist in this world—
Then why couldn't this world's troll fuse with trolls from other worlds?
After all, they were the same species.
Unlike the trolls of the Harry Potter world, trolls in worlds like Warcraft, DND, or The Witcher were famous for their regenerative abilities.
Their wounds healed incredibly fast. Even if they lost limbs—or even their heads—those severed parts could still remain active.
Some trolls could even reattach their limbs directly.
Even more horrifyingly, if they didn't, those severed limbs could continue fighting on their own.
You might see a crawling hand, a hopping leg, or even a biting head on the battlefield—until the troll reattached them or grew new ones.
Clearly, the troll before him had gained this very ability.
If an ordinary troll in this world had combat strength equivalent to a level 5 or 6 opponent,
Then this one—with both high magic resistance and troll-like regeneration—was easily comparable to a level 7 or 8 wizard.
However, such regeneration wasn't without weakness.
Lewis's knowledge from other worlds told him that only strong acid and fire could suppress a troll's regeneration.
"Perfect timing," Lewis sneered confidently.
"I just finished developing Fireball."
As he spoke, he waved his wand and cast the spell he had just learned today.
"Summon Monster."
In an instant, a massive North American bison appeared, blocking the troll.
The bison was just a normal beast and couldn't withstand many blows from the troll.
But as long as it stood, the troll wouldn't be able to threaten its summoner.
Watching the troll get blocked and bellow in frustration, Hermione's eyes lit up.
"So that's how the Bison Spell can be used? That's amazing!"
But Lewis wasn't finished.
Taking advantage of the troll being held at bay, he began casting his second spell.
"Scorching Ray!"
A blazing orange beam, almost white with heat, shot from the tip of his wand and struck the troll directly.
The impacted area instantly charred black, smoke rising from it.
"ROAR—!!"
Already weak against fire, the troll howled in agony as the intense heat burned into its flesh.
The beam carved a deep, straight scar across its chest.
The troll was in such pain that it ignored the bison entirely, clutching its wound and rolling on the ground.
But that was only the beginning.
"Scorching Ray!"
Another blazing beam shot out—this time aimed at the troll's newly reattached arm.
Under Lewis's precise control, the ray struck the joint where the arm had been reconnected and slowly sliced through it.
The freshly regrown connection was already fragile, and under the heat, it was severed instantly.
The arm was cut off once more.
The poor troll was back to being one-armed.
After losing its right arm again, it wailed and picked it up with its left hand, trying to reattach it once more.
But this time, its regeneration had been suppressed by fire.
No matter how many times it tried, nothing happened.
The dumb creature had no idea why. It could only repeat the same futile attempt over and over, roaring in frustration.
Meanwhile, Lewis had finished preparing his final spell.
"Fireball!"
Normally, he wouldn't use such a large-scale destructive spell in a confined space like this.
But trolls were notoriously tough.
Among the spells he had, this was the only one capable of delivering a decisive blow.
After casting it, Lewis immediately stepped in front of Hermione, shielding both of them with Frost Armor.
Boom!
The moment the blazing fire element struck the troll, it erupted into a violent explosion.
Flames burst throughout the entire bathroom.
Even though Lewis stood seven to eight meters away from the center, the shockwave still consumed most of his Frost Armor.
When he looked again, the troll was already lying on the ground, its body charred black and lifeless.
If Lewis hadn't dismissed the Summon Monster spell beforehand, even the North American bison would have been roasted whole.
"Whew… finally done."
Looking at the mountain-like corpse, Lewis wiped imaginary sweat from his brow.
Frost Armor not only protected him but also regulated temperature—sweating in this situation was actually quite difficult.
Hermione also exited her invisibility and stood beside him, staring at the dead monster with lingering fear.
If Lewis hadn't arrived in time, she didn't dare imagine what would have happened.
A few seconds later, hurried footsteps echoed outside the bathroom, followed by familiar voices.
"Hermione! Are you in there?"
It was Harry and Ron—they had come to find her as well.
"I'm here!"
Hermione called back.
The fact that they had remembered to come for her moved her deeply. These two really were loyal friends.
But the one who moved her the most was still Lewis—the one who had come to her first.
No one else made her feel safer than he did.
"Hermione, be careful! There's a troll nearby—ah! What is that?!"
Harry and Ron rushed in, only to be instantly shocked by the troll's corpse.
Before Lewis could explain, more footsteps approached.
Moments later, Professor Flitwick and Professor McGonagall arrived first, followed by Snape, and finally Quirrell—who had apparently regained consciousness.
Quirrell took one look at the charred troll corpse, let out a weak sob, clutched his chest, and dramatically collapsed to the floor again.
Snape bent down to examine the troll, while Flitwick and McGonagall looked at the four young wizards.
"Mr. Lewis Green, what on earth were you students playing at?" McGonagall demanded, her voice cold with anger. "You're lucky you weren't killed. Why didn't you follow instructions and stay in your dormitories?"
"I didn't hear any warning."
Harry and Ron were flustered by the questioning, but Lewis remained completely calm.
He had already prepared for this.
"I just ate too fast at the feast and felt a bit unwell, so I came out to use the bathroom. I didn't hear any warning."
Then he pushed further, turning the question back on them.
"I didn't expect to encounter a troll in a place that claims to be the safest in the world. I'd like to ask—what exactly is the school doing?"
Snape cast him a suspicious glance, as if evaluating whether he was telling the truth.
Meanwhile, Flitwick asked with concern, "Lewis, are any of you injured?"
After receiving a negative answer, he turned to McGonagall. "You've misunderstood, Minerva. Miss Clearwater just told me about Lewis—he did leave the feast early. It's normal that he didn't hear the warning."
"Oh—if that's the case… then I apologize, child. This is indeed Hogwarts' oversight."
McGonagall looked slightly embarrassed. Her anger had come from concern for the students.
She then turned to the three Gryffindors, waiting for their explanation.
"Miss Granger stayed here because she was upset," Lewis explained for Hermione. "She didn't attend the Halloween feast at all. As for Harry and Ron…"
He glanced at them.
"We came to find Hermione!" the two blurted out. "We wanted to warn her about the troll. In fact, we only arrived a little earlier than you professors!"
After hearing everyone's explanations, McGonagall's expression softened.
"I believe I understand the situation now." She cleared her throat and first turned apologetically to Lewis. "Mr. Green, you dealt with the troll alone. For that, I will award Ravenclaw twenty points. I must say, very few first-year students could face a fully grown troll. You've proven your talent."
Flitwick also looked at the charred corpse and praised him. "Although I don't know how you managed to defeat a troll with fire magic, I must say—well done!"
"As for you," McGonagall said, turning to the other three, "Miss Granger, given your circumstances, I won't deduct points. But Mr. Potter and Mr. Weasley—you will each lose five points for Gryffindor. Next time, you should seek a professor instead of risking your lives. If Mr. Green hadn't been here…"
She didn't finish the sentence.
She didn't want Lewis to take it as encouragement.
"Now, you'd best return to your common rooms. The other students are still enjoying the Halloween feast."
On the way back, Lewis had to deal with Harry and Ron's constant questions.
They simply couldn't imagine that someone their age could defeat a troll head-on.
As for Hermione, she walked beside them with a smile on her face—completely unlike the terrified girl from earlier.
For the first time at Hogwarts, she felt the warmth of friendship.
Especially from Lewis.
Only today did Hermione truly feel that she had made a real friend.
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