Felix gently rubbed the inside of his wrist, where there was a flesh-colored pattern the size of a fingernail. If you didn't zoom in and look carefully, few people would notice this pattern.

This pattern is actually an ancient magic rune circuit, with a small space hidden inside.

In the space, there is a spare wand.

After all, the pattern is too small, and there are not many things that can be hidden. Moreover, this ancient magic rune circuit has actually been in a closed state, and can only be opened when conditions are met.

And the condition for opening is to apply a layer of his own blood.

This is his most secret and most difficult to detect back-up plan at present -

when one day he is in a disadvantageous position, or is disarmed, loses his magic wand, or even his ring is taken away, this magic rune circuit will help him turn the tables. As long as he

is not killed on the spot, he has a chance to turn defeat into victory.

The ring on the left hand is bright, and the magic rune circuit on the inside of the right wrist is dark, one bright and one dark, almost perfect.

And now, Felix is ​​also preparing to complete the construction of the third cave.

The reason for being so cautious was not because Hogwarts was a dangerous place, hiding some great danger, or what he was going to do, but because he knew that when he became the professor of ancient magic at Hogwarts, he would officially be involved in the "plot".

With his shallow understanding of the plot, it was difficult for him to foresee the future, so he had to take precautions early.

He did not believe in the so-called "fairy tales", but only believed in his own strength.

However, no matter how little he understood the plot, he still knew some of the most basic things.

For example, eight movies were made about Harry Potter's adventures in his previous life. According to one movie per school year, it would take eight years in the magic world. This was in line with Felix's imagination: seven years of adventures in school, plus one year after graduation to completely defeat the mysterious man, no problem.

Very rigorous reasoning.

Now a school year has passed, and if nothing unexpected happens, Voldemort will be completely dead in seven years.

Thinking of this, Felix felt a little relieved.

Of course, he is not Voldemort's opponent now, but the future is hard to say.

While planning future strategies, Felix went out and walked on the streets of London.

Half an hour later, he stood at the door of a dentist's office - the same one he had discovered a month ago.

Felix pushed the door open and the door bell rang.

A middle-aged man in a white coat poked his head out from the inner room. He looked at Felix and asked, "Are you here to see the dentist?"

Felix replied briefly, "I want to fill a tooth."

The dentist nodded and led him to a chair, "Please sit down. My name is Will Granger, you can call me Dr. Granger."

"I'm Felix Hepp."

Dr. Granger asked him to lie on the chair and looked at Felix's mouth with something like a searchlight. He looked a little confused, "Mr. Hepp, your teeth are in good condition, very clean and neat, and the size is very symmetrical..."

Felix pointed to the upper left side of his cheek, "I want to fill a wisdom tooth."

Dr. Granger was stunned for a moment. This was really a strange request. Wisdom teeth are not very useful. He said sincerely, "Mr. Hepp, I don't recommend you to fill a wisdom tooth, because..."

Then, Dr. Granger showed his professionalism and talked to him about dental knowledge for a full twenty minutes.

During this time, a little girl with fluffy hair came in. She was about twelve or thirteen years old. She looked at the two of them, especially when she saw Dr. Granger's endless performance, and showed an expression of "here we go again".

Finally, Felix had to interrupt him, "Dr. Granger, how about this, you can help me make the tooth first, and I will decide whether to fill the tooth after trying it."

Dr. Granger thought about it and thought it made sense. He took out a pen and paper to record the size of Felix's mouth. After gesturing on the paper, he quickly confirmed the size and shape of the wisdom tooth.

Then he walked into the back room and started working.

Felix looked at the furnishings of the clinic with interest, especially one of the walls was full of small cabinets, and the enlarged tooth model could be clearly seen through the glass.

Just as he was concentrating on it, a confident voice appeared on his left.

"Filling a tooth is not the best choice, especially for a wisdom tooth that is dispensable."

Felix turned his head and looked at the little girl, and then heard her add, "It will hurt."

"Hurt a lot? How much?"

"You need to drill a hole in your gums with a small drill, and then drill a hole in your artificial wisdom tooth, connect it with screws, and then re-fix and adjust the position."

Felix suddenly had a toothache...

and the little girl continued to popularize science, "Even if the tooth is filled, it is not a permanent solution. On the contrary, after the gums are damaged, they will be more vulnerable to damage. Even if you have bad oral habits on weekdays, it will cause the gums to rot and plaque, causing the original teeth to loosen and fall off, and must be repaired again..."

"Stop talking!" He already had a picture.

Although he could use magic to repair and relieve pain, his heart was traumatized now.

Looking at Felix's uncomfortable expression, the little girl shook her fluffy long hair and ran to the corner to read a book. It can be seen that she seemed to be in a very happy mood.

After nearly twenty minutes, Dr. Granger came out again.

In his palm, he dragged a silver tray, on which was an artificial tooth that had been polished and modified.

"Looks great, right?" Dr. Granger praised his craftsmanship.

But Felix simply nodded. He was shocked by what the little girl had just said!

Following Dr. Granger's instructions, he tried the artificial wisdom tooth. Of course, there was no drilling or wire wrapping. He just tested the comfort level.

"Very good!" Felix praised. "But I decided not to fill the tooth anymore."

"Really? It seems you made the right decision." Dr. Granger was not angry about losing a business. Instead, he was happy for him.

But the customer made a new request, "I want to buy this tooth as a souvenir."

"A memorial?" Dr. Granger thought. Even the little girl who was reading quietly beside him looked up at him.

"Yes, a memorial."

"Okay." In the end, Dr. Granger only charged for the materials.

As Felix walked out of the clinic, Dr. Granger still felt something was wrong. He complained to his daughter, "A very strange customer, don't you think, Hermione?"

Hermione Granger looked up and watched Felix disappear at the corner of the street. She shook her head and lowered her head to read again.