Nicolas Flamel

"Deprimo Profundis" is the incantation for the "Falling Spell," a 1832 improved version from the Hogwarts Duelling Club.

At the time, this so-called modern Levitation Charm was widely used due to its simplicity, even being abused as a tool for pranks.

A certain Head of House from Ravenclaw deconstructed the spell in reverse, discovering that "making an object rise" and "making it fall" were essentially different waveforms of the same gravity interference command.

It is said that when she wrote down the derivation formula for this "Deep Falling Spell" on parchment, the ink suddenly seeped vertically into the grain of the wooden table, all the way to the floor of the third story, which cracked.

The specific casting motion for this spell is the opposite of the light, upward flick of the wand used for the Levitation Charm. The Falling Spell requires the wrist to chop downwards, as if smashing an invisible giant hammer onto the target's center of gravity.

Its effect is that the mass of the struck object briefly increases exponentially, while its volume remains unchanged—a feather can leave spiderweb cracks on a wooden floor, and a book can bend a bookshelf.

If the spell is cast on an object already affected by the Levitation Charm, the two forces will create a brief period of static suspension, after which the object will fall downwards at double the speed.

The wizarding world still debates whether this spell should be classified as "Dark Magic."

The troll blankly raised its small head, disproportionate to its nine-headed body. The next second, the heavy weapon, whistling through the air, smashed fiercely onto its own bald head.

"Bang!"

The troll swayed a few times before crashing to the ground, shaking the very floor.

Harry and Ron stared dumbfounded at the scene before them, completely baffled as to why Ron's spell had suddenly become so effective. Hermione crawled out of the compartment, her face pale and her body trembling, but she still looked around.

"Stop looking! Let's go!" Harry pulled Hermione up.

The three stumbled out of the corridor and ran straight into Professor McGonagall and others who had rushed over upon hearing the news. Yulian, meanwhile, had already slipped away into the darkness on the other side, making a quiet exit.

He knew that Quirrell's plan for the night had failed. The Philosopher's Stone was safe, and the stone slab seal had not been disturbed. As for himself, in a corner unknown to anyone, he had become... a watcher?

He cast one last glance at his friends, who were being sternly reprimanded by the professors but were otherwise unharmed, and a smile of relief touched his lips.

The next morning in the Hogwarts Great Hall, the air was, as usual, filled with the aroma of toast, bacon, and butter.

But today, even more potent than the scent of food was the rising tide of discussion: the story of Harry, Ron, and Hermione bravely fighting a troll had spread throughout the castle overnight, as if by a Speed-Spreading Charm.

"Did you hear? Three first-years from Gryffindor actually took down a troll!" Hannah Abbott exclaimed with wide eyes at the Hufflepuff table, her voice full of amazement. "Ron used the Levitation Charm to lift the troll's club and knocked it out!"

"And Hermione!" added Justin Finch-Fletchley beside her. "She wasn't panicked even when trapped in the girls' lavatory and was guiding Ron's spell!"

The Gryffindor table was even more jubilant. Percy Weasley straightened his back and detailed his brother's "heroic deeds" to those around him, his face beaming with pride.

Harry, Ron, and Hermione were surrounded, receiving praise from students of all years, their cheeks flushing slightly.

"Headmaster Dumbledore himself awarded Gryffindor thirty points!" a senior Gryffindor student shouted. "Now our lead over Slytherin has shrunk considerably!"

Amidst the cheers, the Slytherin table was silent. Draco Malfoy scowled, his silver fork and knife clenching in his hand until they creaked. He stared intently at Harry, who was being mobbed by the crowd, jealousy practically overflowing from his eyes.

"It was just luck!" he muttered spitefully to Crabbe and Goyle. "A mudblood, a poor kid from the Weasley family, and a Savior who doesn't live up to his name—and they deserve points?"

Crabbe and Goyle nodded repeatedly but dared not openly agree. The incident of the troll rampaging through the castle last night had not entirely subsided, and they had no courage to publicly question the Headmaster's decision.

In a corner of Ravenclaw, Edgar Finch pushed up his glasses and glanced suspiciously at Yulian, who was leisurely slicing his sausage beside him. "Say, Yulian, were you really in the girls' lavatory last night?"

Kayson Moretti leaned in, his face full of curiosity. "Yeah! And... Ron usually can't even keep a feather steady, how could he suddenly lift a troll's club?"

Yulian looked up and offered an innocent smile. "Maybe he unleashed his potential in an emergency? As for me," he shrugged, "I probably took a wrong turn and followed the crowd back to the dormitory. You just didn't see me."

Edgar was about to press further, but Kayson pulled him back. "Forget it, forget it," Kayson lowered his voice. "Maybe he really had a stomach ache! But speaking of which, Gryffindor's luck is just too good, getting thirty points!"

Yulian smiled and offered no further explanation. He knew his roommates' suspicions were not unfounded, but some things were best left unsaid.

After the troll incident, the relationship between Harry, Ron, and Hermione became exceptionally close. Past minor squabbles vanished in the face of their shared near-death experience, and the trio became almost inseparable.

However, they were often seen huddled in a corner of the Gryffindor common room, or in a secluded area of the Library, discussing something in hushed tones, their eyes full of mystery.

Yulian occasionally caught glimpses of them gathered around a crumpled piece of paper, arguing softly, or whispering over a thick, ancient tome. He understood that they must be pondering the three-headed dog guarding the forbidden zone on the fourth floor and the secrets hidden behind it.

One afternoon, after finishing his History of Magic class, Yulian was strolling along the path by the Black Lake on his way back to the Ravenclaw tower. He saw Harry, Ron, and Hermione in the distance. They were walking quickly towards Hagrid's hut at the edge of the Forbidden Forest, their expressions urgent, as if they had something important to ask.

"Looks like they couldn't resist going to Hagrid for information," Yulian stopped, watching their backs disappear through the hut's doorway, and murmured to himself. He knew that given Hagrid's personality, he would most likely inadvertently reveal more clues about the three-headed dog and the Philosopher's Stone.

As expected, after returning from Hagrid's, the trio increased their research frequency. They spent more and more time in the Library, poring over all sorts of books on magical creatures, ancient treasures, and modern wizards.

One evening, Yulian was in the Library researching star magic when Hermione quietly approached him, her expression somewhat tentative. "Yulian, have you... have you heard of Nicolas Flamel?"

Yulian looked up and blinked, feigning surprise. "Nicolas Flamel? Yes, I have."

"What! You know him? You're not joking?!" Hermione was genuinely startled now.

"Doesn't everyone know him?" Yulian said, pointing to a Chocolate Frog wrapper in his pocket. "Isn't he on the Chocolate Frog cards? He's the greatest alchemist, invented the Philosopher's Stone, and lived for hundreds of years."

Hermione's face lit up with realization, her eyes instantly sparkling. "Right! The Chocolate Frog cards! How could I not have thought of that!" She quickly said "Thank you" and turned to run towards Harry and Ron, who were waiting not far away. The three immediately huddled together and began whispering.

Yulian watched them go, a faint smile playing on his lips. He knew that the truth about the Philosopher's Stone was slowly being revealed to them, but this was the trajectory of fate, and he didn't need to interfere too much.