From Azkaban to Hogwarts.

'If I can get them all out during the day, fifteen minutes will be enough for me to figure out the layout of the break room pretty much—let me think, how can I get everyone out without leaving a single one behind?'

"Raise."

“Just increase the stakes,” William refined his calculations. “When the reward is high enough, those students won’t suspect anything.”

'The password isn't a major issue; it wouldn't be too easy for a professor to find out. No student would be wary. Of course, to prevent any accidents, it's best to find out the password beforehand. The prefects are away these few days, so the lounge password shouldn't be changed.'

What a quiet morning.

William sighed, pulled out his wand, and walked out of his office.

It's four in the morning, the time when people are at their lowest energy level—to be precise, the time when people are most sleepy. Even night owls are already in bed, and even the most diligent students can't possibly get up at four in the morning on holiday to do their homework.

'If I run into anyone, my excuse will be that I can't sleep and I'm doing a night check.'

William walked slowly down the corridor, pondering how to deal with being discovered.

'There are no oil paintings nearby for surveillance. I can go down to the secret passage in the next corridor. I've investigated that area before; as long as I don't leave any footprints, it'll be fine.'

The shoes enchanted by the spell made almost no sound when they stepped out; even in the empty castle, no sound could be heard. This made William truly realize that he was doing something wrong.

'Breaking into the Slytherin Headmaster's office? Nobody would believe it even in Azkaban, right?'

William opened the secret passage with ease and skill, magically restoring the dust as he went—thanks to the two previous checks, his technique was second nature.

'So why did Professor Snape choose the underground classroom? It's cold and damp.'

The thought of walking down the secret passage involuntarily popped into William's mind.

He had never been to Professor Snape's office, but that wasn't difficult; he had been in the castle for a week, after all.

'arrive.'

William checked briefly, then stepped out of the secret passage and closed the door—there was an oil painting on the way to Snape's office, but it wasn't a big problem; a Disillusionment Charm could easily solve the issue.

Having easily dodged the painting that was still dozing off, William arrived at his destination with ease.

'It's just an ordinary door, but I can sense the power of dark magic hidden within it.'

William maintained the Disillusionment Charm and carefully examined the door. 'This is strange. Although I've never seen magic like this before, its power is too weak; it can't kill anyone at all.'

'This magic, well, it's a mark-printing magic. If someone trespasses, a mark will be placed on their face.'

'This is reinforced... I'm not sure, the spell is too subtle.'

William wouldn't normally be able to distinguish things so carefully, but the door was shrouded in dark magic. By following the aura emanating from the dark magic, he could easily pinpoint the attached spells.

'The protective measures are excellent, but the lethality is completely inadequate...' William made his judgment, then chuckled at his own assessment. 'I forgot about defusing the bomb. This is a school. In the event of an intrusion, protective magic killing students could be fatal.'

If it's not very lethal, then it's easy to handle.

William enthusiastically cast protective spells on himself. Although he admitted that Professor Snape was temporarily ahead of him in ordinary magic, memory magic, and dark magic, there was no doubt that Professor Snape's level was not much better than his student's in a series of special spells such as picking locks, destroying traps, and dispelling defensive magic.

'It's just that the protective spell is a bit stronger—I was even thinking of using a card, and this is it?'

If the spring strength of a lock remains unchanged, then no matter how big the lock is, it will only protect against a fool who tries to cut the lock.

'Hmm, let's try this one first.'

William pulled a small knife from his pocket, preparing to test the strength of the protective magic.

'If I change the spell, the protective spell will most likely melt the knife,' William muttered to himself, inserting the modified knife through the crack in the door and then tapping the door with his wand.

'Sizzle.'

The knife melted like butter halfway through the slide, but instead of flowing down the door crack, the molten metal gushed out and solidified into a long, grayish-black strip.

The alarm magic was triggered almost simultaneously, but William easily intercepted it.

'Traditional methods, only the intensity is high enough…'

William silently assessed the situation, then took out a key and inserted it into the lock—another protective spell instantly appeared, but as it took effect, William intercepted another protective spell.

That's it?

...

When the tenth protective spell was blocked, William's smile vanished.

'Even Azkaban's cells aren't this outrageous, eleven layers of protective magic! Do you think this is Gringotts' vault?'

He grumbled as he pulled an expensive knife from his pocket, then reluctantly put it away—it would be destroyed if he used it. It cost seventy-five Galleons. He had gotten a whole set of tools out of curiosity when he was ordering teaching aids for class before, but he didn't expect it wouldn't be enough to wreak havoc today. Who would add that much protection to a normal person's gear?

The rest were cheap, but this one was ridiculously expensive, and he was a little reluctant to part with it.

"Use the white card, the success rate is so low—anyway, all the alarms are off, so failure won't matter, and success will save you money."

The Azkaban prisoners provided him with a bunch of low-success-rate white cards, mostly related to fraud or theft, which were useless anyway, so tearing them up now would save him the trouble.

This was, in a way, the first time he had used a card that had a real-world effect. But since he didn't care, William destroyed one without any ceremony.

'Make the unlocking charm even more powerful?'

This feeling came over him, like the feeling he had experienced after drinking Felix Felicis, as described in the records he had read.

'Let's give it a try—'

This strange feeling made William realize that a special power, as if he could try to exist in a new way, had suddenly emerged—so he kept his right wand firmly pressed against the door, controlling the suppressed spell, while his left hand slowly extended and touched the door lock.

"Araho Cave is open."

He whispered the incantation.

Chapter 189: Guesses Come True

Successful.

Moreover, it is a staffless spellcasting technique that William has not yet mastered and is commonly used in emergency situations.

'This is the low-success-rate white card? Are you kidding me!'

William tried to relive that magical feeling, but it was nowhere to be found—the power vanished the moment the lock opened silently.

"It makes you want to tear up another card and try it out."

William muttered something under his breath, then quietly opened the door, his wand sliding down the doorway while maintaining control of the magic, and slipped inside on tiptoe—even if he were stupid, he wouldn't experiment in front of this open door; that would be idiotic.

'The door can't be closed. If it is, the magic will take effect, and even picking the lock from the inside won't be easy.' Following his pre-prepared plan, William took out a piece of wood wrapped with magic tape from his pocket and sandwiched it between the door and the door frame.

This kind of magic tape is also called magic tape. It is generally used to repair magical items, but the effect is not very good. However, because of its working principle, when blocking a door, it will make the door think that it is locked properly - a little trick from Azkaban.

"Time is running out. Although the underground classroom area is usually deserted, I still need to hurry."

William urged himself on as he quickly checked the house for any light- or sound-sensitive traps. After all, a long holiday is different from a normal day, and he would have placed more traps in the house if it were him.

'No?'

After checking around, William frowned in confusion—did Professor Snape think his protective magic was superior or his defensive methods were so clever that he couldn't detect it?

Although time was tight, he patiently checked the room again.

The result was the same as at the beginning: nothing was gained.

'Alright,' William shook his head, raised his wand, and a bright white orb flew out of his wand, illuminating the surroundings.

He added soundproofing and light-blocking magic to the wooden planks at the doorway. Although there was a risk of being caught by outsiders, it also prevented the possibility of an alarm trap inside the house that could not be dealt with immediately, thus revealing his whereabouts.

'It's so dark, it's practically a place without any natural light.'

William surveyed his surroundings, trying to find the darkest spot—most people have a habit of hiding things in the darkest or behind the brightest places.

Unfortunately, although some areas illuminated by the ball of light were sparkling, it was merely a reflection from the glass jar.

Yes, glass jars. In Professor Snape's office, there were many shelves filled with large glass jars containing all sorts of specimens.

'Salamander entrails?'

'Is this a prickly fellow?'

...

Most of it consisted of potion ingredients, and quite rare ones at that. The remaining small portion—William guessed it was still potion ingredients, but potion masters of his caliber had never even touched them…

'That's outrageous. Even if it's just potions, having them all out like that is kind of creepy.'

William couldn't help but think of the stack of jars that appeared at the beginning of the novel "The Deer and the Cauldron" and couldn't help but laugh out loud.

'Is it going to be some kind of hidden door created by moving a jar, like in traditional martial arts novels?'

William waved his wand, and the jars he pointed at all floated up about a centimeter.

"No problem, next batch."

He quickly pointed his wand at the other jars.

On the tenth attempt, it got stuck—one of the jars wouldn't float; the magic spell wasn't pulling hard enough.

'No way, there really is a hidden room? This is just the beginning!'

William glanced at the desk and bedroom that hadn't been searched yet, and a smile involuntarily crept onto his face.

So the jars in the office were just a cover for a trap? Putting potion specimens in the jars is disgusting yet not out of place—someone like William, who knows his stuff, would immediately recognize them as potion ingredients.

He instinctively covered his face. He had been thinking about how to crack the bedroom's mechanism, and this was the result.

Disheartened, William used magic to blow the dust back onto the jar he had previously moved, and walked to the jar of potion specimen that he couldn't move.

Specimens of the hunchbacked tree are almost worthless, and dissected specimens are so unsightly that almost no one wants to touch them.

Twist the glass jar, and a wall collapses behind you, revealing a passageway.

That's too traditional.

William shook his head and went inside. There couldn't possibly be any other mechanism at the entrance. If the magical fluctuations were too great, why would they build a secret room? It would just be an obvious sign that something was wrong.

'Professor Snape's trap-setting skills need improvement—holy crap!'

It's no wonder he was so surprised; the very first thing he saw was terrifying enough.

A huge photograph, almost as tall as a person, was placed there. The person in the photo was smiling gently and looked very shy. His green eyes were staring intently at William, which looked quite frightening.

But the problem isn't the photo itself, it's the person, Harry Potter!

What an international joke!

Why is there a picture of Harry Potter in Professor Snape's Chamber of Secrets?!