Tewell's face changed instantly.
But by the time he drew his wand, it was too late; Quirrell was too close to Harry— "Avada Kedavra!"—the green light was upon Harry in an instant.
Facing the green light, Harry froze as if he was paralyzed, only able to watch helplessly as the green light pierced through the sudden appearance of the first and second layers of his Shield Charms, then ding, it hit the last layer of golden film before dissipating altogether.
(Just a little reminder: Ordinary Shield Charms can't block Unforgivable Curses; only extremely powerful ones can, so everyone, don't try to resist the Killing Curse casually!)
"Oh?" Quirrell only noticed the three badges Harry was wearing now.
After enduring such an attack, one of the badges was notably dimmer, while the other two were also dimmed to varying degrees.
"Fawley's got quite a few tricks up his sleeve, but just a few badges won't save you!"
Quirrell sneered at Harry, his wand in hand relentlessly releasing another Killing Curse.
Under the shadow of death, Harry trembled all over, trying twice before he managed to draw his wand, but he could only watch as the Shield Charms on his body were broken.
"Expelliarmus!"
"Huh?" Quirrell curiously felt the pressure coming from all directions; it wasn't strong, but it slowed down his movements, making his wand swings slightly delayed.
"It seems Fawley taught you a lot of good stuff."
"Professor is a million times better than you!" Suddenly, a red light flashed from Harry's wand, accurately hitting Quirrell's eyes.
It was quite effective; Quirrell's eyes flickered for a moment, immediately covering them and groaning in pain.
Unfortunately, it was only a flash.
"Reducto!"
The stairs beneath them were instantly blasted apart; Harry, who had intended to take the opportunity to escape, was thrown away by the force of the blast.
Harry was dazed by the impact, flying high in the air, and it was a while before he came to his senses.
"Why am I floating in the air?" He looked puzzled at the ground several feet away.
Then he slowly drifted towards the direction of the door, where Professor Fawley, hands clasped in front of him, was smiling at him.
"You did great; leave the rest to me."
Harry's face lit up, but before he could speak, he passed out and drifted out slowly.
Meanwhile, Tewell took out the Philosopher's Stone from his pocket and put it into his own.
Quirrell didn't stop him but watched Tewell approach with a smile on his face, as if he was out for a stroll.
"Why bother? We're villains; we should have some bottom line," Tewell said earnestly, "the Philosopher's Stone is in his pocket; you can just take it."
"Bottom line?" Quirrell sneered, "My bottom line is my master's command!"
Hearing this, Tewell couldn't help but show a meaningful smile, leaving Quirrell puzzled.
"All this talk about masters, masters, easily gives people the wrong idea about your... peculiar relationship."
He frowned, pondering for a moment, but couldn't understand the meaning behind Tewell's words.
"Enough talk, hand over the Philosopher's Stone, or you'll die in place of that brat!"
The smile on Tewell's face disappeared instantly, no extra movement in his body, but it brought immense pressure to Quirrell.
"Are you sure?"
"I'm sure!"
Unexpectedly, it wasn't Quirrell who said this, but Voldemort at the back of his head!
"Mas—ah, aahh—"
Before Quirrell could finish his sentence, his face seemed to melt, twisting continuously, and he screamed in agony, curling up on the ground.
Tewell's heart trembled at the sound.
Soon, Quirrell's screams ceased, and he stood up again.
But at this point, he couldn't be called Quirrell anymore.
Tewell scrutinized the face of "Quirrell," on which it seemed like another face was superimposed, overlapping on the same head.
"So, you've been draining Quirrell's life force all this time just to take over his body today?" Tewell asked.
Quirrell, or rather Voldemort by now, grinned widely, his mouth moving involuntarily, as if adjusting to this new face and body.
"Quirrell was always meant to die; giving him a chance to sacrifice himself for me isn't that nice?" Voldemort spread his hands, the wand held casually in his right hand.
"The question is, what are you doing all this for?" Tewell observed Voldemort's current body, which was quite dissonant, with skin even showing signs of peeling.
"Killing me to steal the Philosopher's Stone? But Quirrell's body won't hold for much longer, and when it collapses, you still won't be able to take the Stone with you."
"No, ever since I realized Dumbledore was constantly monitoring this place, I knew that neither you nor Quirrell would be able to take the Philosopher's Stone," Voldemort said smugly.
Tewell's expression turned serious.
In his plan, he feared Dumbledore the most.
"I bet you don't even know what Dumbledore released here?" Voldemort pointed at the surrounding torches.
"He doesn't need to set up detection spells; just by using the characteristic of the magic torches lighting up when people approach, he can monitor this room," Voldemort explained proudly.
Tewell suddenly understood, even feeling a bit helpless as he chuckled.
Truly worthy of Dumbledore, always able to utilize things others didn't notice and achieve incredible effects.
In a way, he had reached a state of being back to basics.
"So why don't you run away now and wait to be caught by Dumbledore?"
Voldemort shrugged playfully, or rather smiled, though for him, it was a "playful" expression.
"Anyway, I can't die, so you should be the one worried, right?"
"What do you mean?"
"I've done so much just for you, Tewell Fawley!" Voldemort walked up to Tewell, eyeing him admiringly.
"I've never seen a young man as talented as you; join me, and with your help, not only can I easily come back to life, but I can also easily kill all the resistors and create an era that belongs only to us!"
He became more and more excited as he spoke, but his pale face showed no trace of color, looking extremely eerie.
Tewell's inner self remained unmoved, even finding it amusing.
"But you've wasted so much of my time; how am I supposed to escape when I encounter Dumbledore later?"
"With so many students in the school, we can always catch one or two; when the time comes, we'll just run however we want," Voldemort said nonchalantly.
Tewell sighed disappointedly.
"Years of wandering haven't taught you that you should learn to use more sophisticated methods?"
Voldemort was taken aback for a moment, blinking blankly, "Why bother with more sophisticated methods?"
"You see, that's the difference between you and me; I've never deigned to use these despicable means because I'm far smarter than you." Tewell shook his head in mock disappointment.
Realizing he had been mocked, Voldemort narrowed his eyes slightly, "Then let this despicable person teach you a lesson!"
"Really? Destroy if you can't obtain?" Tewell taunted.
"That's my plan," Voldemort said, taking a step back to create some distance for spellcasting, "if you don't join, then I'll delay you and destroy you with Dumbledore's help."
"You call this a sophisticated method?" Tewell chuckled.
Finishing his words, Voldemort even made a mock bow.
Tewell chuckled as he watched him, giving a flawless bow in return, saying, "But how long can you delay me like this?"
Before he could steady himself, Voldemort sent a Killing Curse flying towards him, but Tewell easily dodged it.
In response, he sent three consecutive Killing Curses!
Meanwhile, at Voldemort's feet, the stone slabs seemed to melt away, instantly transforming into a swamp.
In a careless moment, Voldemort's feet sank into the ground, but with a wave of his wand, three black snakes flew out in front of him, blocking the Killing Curse.
He continued to brandish his wand, and a snake head made of mud lifted him up from the swamp.
However, the next moment, this snake head was shattered by Tewell, splattering Voldemort with mud.
"Sorry about that, making you look so bedraggled,"
Voldemort said, glancing at the mud stains on himself. Although it wasn't his body, he, who was always so proud, had never endured such humiliation.
"I only intended to delay you a bit, didn't expect you to—"
"Snap."
He raised his wand to block Tewell's curse.
"Even my students know that when fighting, you shouldn't talk too much. Hasn't your teacher taught you these things?"
Even as he spoke, Tewell didn't stop his magical onslaught against Voldemort.
"You bastard!"
Voldemort retaliated with a Killing Curse, his face flushing slightly with anger, looking even more sinister.
Tewell calmly blocked it. "Be more elegant, Tom. This is a rare duel that can teach you a lot."
"How dare you?!"
Voldemort hated someone's mouth for the first time, more than the curses being hurled at him.
"When in battle, don't let your emotions control you. Calmness is your greatest weapon. That's a little lesson from Professor Fawley just for you."
"Go to hell, you bastard!"
Dismissing his idea of stalling, Voldemort summoned all his remaining life force and magic, waving his wand. The broken walls in the room, shattered by spells, split open, and various large and small fragments were swept together.
In an instant, a tornado made of mud took shape, rushing towards Tewell with a roaring sound.
"Boom—"
The earth tornado struck where Tewell was standing, and the swirling smoke spread outward, obscuring Voldemort's view of the situation inside.
After a moment, all the smoke seemed to be sucked together by a giant vacuum cleaner.
"Just a reminder, size doesn't always correlate with power. In fact, it can often lead to magical dispersion, which isn't advantageous in a one-on-one fight,"
Tewell's voice echoed as his figure emerged. He raised his wand towards the tornado overhead.
"Also, refrain from using magic that pollutes the environment. Look at all the PM2.5 levels skyrocketing here!"
As he finished speaking, the tornado, like a gentle autumn breeze, blew towards Voldemort.
But the wind's range was too vast, and in this place where he couldn't apparate, he couldn't escape, only helplessly watching as the tornado engulfed him.
The dust instantly covered him, cutting into every inch of his skin like blades, slicing his body into pieces.
What was even more terrifying was that although this wasn't his body, Voldemort could still feel the pain from the soul level.
Feeling torn apart, he desperately fled from the shattered body of Quirrell, forming a wisp of black smoke flying towards the exit.
Behind him came Tewell's final words, "Tom, please remember one last thing—immortality of the soul doesn't mean the absence of sensation. In fact, the soul state can make you experience even more unbearable pain."
Watching Voldemort flee in disarray, Tewell shook his head helplessly, unsure if his student had absorbed his teachings.
But having been a teacher for only half a year, he was surprised to find himself so accustomed to imparting knowledge to others.
He casually glanced at the ashes that had once been Quirrell, unable to distinguish bone from dust.
"Wow, I'm really dedicated to my job!"
PS.
Regarding the Philosopher's Stone plan, in fact, I've devised different thoughts and strategies for each of them.
Dumbledore sensed someone's intention to steal the Philosopher's Stone, so he tested it out at Gringotts and, once confirmed, set up this trap, actually monitoring the situation all along.
Tewell, on the other hand, planned to help Quirrell retrieve the Stone, escape Hogwarts, then seize it back after eliminating Quirrell. Without evidence after Quirrell's demise, Voldemort wouldn't expose him during a casual tea with Dumbledore. Thus, with an alibi, at most, he'd be seen as a coerced accomplice.
Voldemort initially sensed the trap and used Quirrell as a decoy to test it. However, upon realizing Dumbledore's attention to the Stone, he promptly abandoned the plan and shifted focus to thwarting Tewell, preventing the potential future encounter between Dumbledore and a revived Tewell.
Quirrell, being diligently committed, was the only one earnestly pursuing his goals. However, he remained manipulated by both Voldemort and Tewell throughout, naively thinking he could confidently walk away with the Philosopher's Stone.
Because the original plot was somewhat intellectually lacking, in order to ensure readability across different age groups, I forcefully enhanced the strategic arrangements for them. Otherwise, writing with the protagonist's intelligence overwhelming would be dull.