Creeeak—
With a soft sound, the wooden door to William's staff quarters was pushed open.
William walked in, carrying the suitcase that was still wobbling restlessly. The room wasn't large, and the air smelled of dust from long disuse.
He didn't rush to put down the suitcase but instead drew his wand.
"Tergeo!"
An invisible current of air instantly swept through every corner of the room. The accumulated dust gathered into a ball as if pulled by a vacuum cleaner, then vanished.
Immediately after, William tapped the four walls lightly. Under the effect of the Undetectable Extension Charm, the originally somewhat cramped single dormitory expanded outward in an instant. The ceiling rose, the walls receded, and in the blink of an eye, it transformed into a spacious and luxurious suite.
Rubbing the silver ring on his finger, several pieces of exquisite mahogany furniture, soft Persian rugs, and a huge four-poster bed appeared out of thin air, automatically settling into their appropriate places.
Looking at the rejuvenated room, William nodded with satisfaction. Only then did he notice that the suitcase at his feet was shaking more and more violently; it seemed the occupants inside had reached the limit of their patience.
"Alright, alright, come on out."
William unlocked the suitcase, and a colorful figure immediately darted out.
This was the only suitcase he had brought. Although the space inside the alchemical ring on his left hand wasn't small, at his current level, he couldn't yet stuff living creatures into it.
As soon as Otto's three heads emerged, they got busy. The left head rubbed excitedly against the carpet, the middle head held itself high to survey the unfamiliar room, while the right head hissed temperamental ly at the fireplace, seemingly complaining about the cramped conditions inside the suitcase just now.
Leaving Otto to explore the new environment, William turned and left the dormitory, heading straight for the Alchemy Professor's office not far away.
Pushing open the door, he found it piled high with various alchemical equipment left by the previous professor. Some looked centuries old; cauldrons had thick grime at the bottom, and glass jars on the shelves contained dried-up herbs and animal organs that had long lost their magical properties.
"Looks like a major cleanup is needed."
William decided to convert this office into his private alchemy laboratory. As for daily office work and receiving students, the still-vacant Defense Against the Dark Arts office would suffice.
After a flurry of activity, William unceremoniously tossed the overly worn and even rusted alembics and scales into the trash, clearing them out along with the aged materials that had long lost their potency.
Then, he took out a brand-new set of high-precision alchemical equipment from his ring, along with a cabinet full of various materials.
Looking at the laboratory shining under the magical lights, William clapped his hands and prepared to head to the next office to set up.
Just as he stepped out the door, he nearly collided with someone at the corner of the corridor.
"Huff... huff... Professor Shafiq." Filch was leaning against the wall, gasping for breath, his wrinkled face flushed with excitement. "All the stone statues... huff... I've finished setting them all up."
"All of them?"
William was somewhat surprised. The total length of Hogwarts' corridors wasn't short; even energetic young wizards would be exhausted after running through them once, let alone climbing up to hang statues one by one.
In his impression, although Filch was a dutiful caretaker, he didn't seem adept at magic and shouldn't have been this efficient.
"Professor McGonagall and Professor Flitwick... they didn't have anything to do just now, so they helped me hang the statues up." Filch wiped his sweat, staring eagerly at William. "That... surveillance book, when can I use it?"
So the professors had helped. That explained it. With the magical prowess of those two professors, hanging statues along a corridor would take mere moments.
"Don't rush, Filch. I still need to go back and calibrate it. I can give it to you before you sleep tonight."
William nodded, then, as if remembering something, pulled a bulging green cloth bag from his robes and handed it to Filch.
"Since you're so efficient, if you don't mind, there's a small favor I need from you."
Filch took the bag suspiciously and opened it to find a pile of lifelike Bowtruckle models and another surveillance book with a cover patterned like tree bark.
"What's this?"
"The purpose is the same as those stone statues, except statues are too conspicuous in the Forbidden Forest. Bowtruckles fit the style there better and aren't easily discovered."
William said, handing over a parchment map marked with several red dots on the edge of the Forbidden Forest.
"Marked on this map are several small paths where it's easy to sneak into the Forbidden Forest. Please take these things to the gamekeeper, Rubeus Hagrid, and have him hang these Bowtruckles on the branches at these locations."
"Our surveillance network needs to cover not just the interior of the castle but also the perimeter of the Forbidden Forest, to prevent reckless brats from running in and feeding the werewolves."
Although he had been away for over a decade, William was confident that he and his peers back then had pretty much discovered all the sneaky routes into the forest. He didn't believe the current young wizards could be more creative than they had been.
Faced with William's request, Filch hesitated.
His relationship with Hagrid had always been poor; they barely spoke.
Filch looked hesitantly at the bag in his hand, seeming to consider refusing this errand. But thinking of the surveillance book he was about to get—the one that would let him see the movements of every student in the school—he gritted his few sparse yellow teeth.
"No problem, Professor." Filch tucked the bag under his arm. "I'll make him hang them up, as long as you can give me that book as soon as possible."
With that, he hugged the items and trudged toward the castle entrance, his back surprisingly radiating a sense of motivation.
William rubbed his chin thoughtfully.
It seemed the surveillance system was even more attractive to Filch than he had anticipated. Normally, given their antagonistic relationship during his student days, even now that he was a professor, the other party shouldn't have agreed to run errands for him so readily.
"No permanent enemies, only permanent interests. That Muggle Prime Minister was right..."
After sighing, William found a deserted corner and summoned the system panel.
[Ding! Detected that the host has improved the security defense system of Hogwarts. Hogwarts construction progress increased. Reward: 200 points.]
Seeing the points credited, William was happy for a moment, but he quickly calmed down.
He had one more thing to verify.
The current coverage density was one every 20 meters. What if he increased the density?
The more surveillance, the higher the security index—that made sense, right?
As a wizard with strong initiative, William immediately took out another batch of spare stone statues from his ring. Instead of waiting for Filch to return, he waved his wand himself and began experimenting in the corridor on this floor.
He first increased the density from the original 20-meter interval to one every 15 meters.
[Ding! Detected improvement in security defense system precision. Reward: 20 points.]
William's eyes lit up as if he had discovered a massive gold mine.
If he could farm infinite points, he wouldn't mind turning the Hogwarts corridors into a gallery full of stone statues, placing a camera every two steps so not even a fly could escape.
He immediately waved his wand again, increasing the density to one every 10 meters.
[Ding! Detected improvement in security defense system precision. Reward: 30 points.]
There's more! Keep going!
William rubbed his hands excitedly and increased the density again, this time directly to one every 5 meters. The entire corridor wall was packed with stone statues, looking almost trypophobia-inducing.
But this time, the system didn't react.
Unwilling to give up, William tried 3 meters, 1 meter, and even stuck two statues together, but the system remained silent.
"It seems 10 meters is the system's judgment limit... Any denser and it's judged as invalid redundancy?"
William put away his wand with some regret. Looking at the few hundred points he had just earned, although he couldn't exploit an infinite points glitch, this harvest was pretty decent.
"One shouldn't be too greedy."
William comforted himself, then waved his wand to recall the excess stone statues into his ring, ultimately keeping the configuration at one every 10 meters.