Felix was very busy on the first weekend of the new school year.

With the first dueling class approaching, he had to decide on the third resident professor as soon as possible. Privately, he asked Flitwick and Professor McGonagall for their opinions.

Professor McGonagall politely declined, saying that she was also the deputy headmaster and had many trivial matters to worry about in the school.

"If it's just one or two occasions, I'd be happy to do it," she said to Felix.

The progress on the other side was very smooth. Almost as soon as he opened his mouth, Flitwick readily accepted the invitation, as if he had been waiting for this day.

From a neutral point of view, Felix also recognized that Flitwick was the most suitable candidate for the professor.

As the person in charge of the dueling class, he had to consider the difficulty and learnability of the spells he taught, because he was facing students from all seven grades in the school.

As an experienced professor of spells, Flitwick undoubtedly mastered a lot of skills to simplify the difficulty of learning spells.

In comparison, Transfiguration has a higher threshold - it is not easy to use Transfiguration flexibly in a duel. It tests the wizard's silent and fast casting and imagination of the duel.

Even for senior students at Hogwarts, it is difficult to perform mature biological transformation silently, not to mention in combat.

"Transfiguration is the field of genius, representing the unconstrained imagination of magic." This is what a dueling master who is good at Transfiguration wrote in a magic notebook. Felix partially agrees with his point of view.

Ravenclaw Dean's Office.

After solving the invitation problem, Felix and Flitwick spent nearly a day discussing the improvement of the "Zooming Spell".

"The performance of the Zooming Spell on magical creatures is not outstanding. Of course, it may also be because the current experimental creature is only one kind of Flobberworm, which is not representative." Felix took out a stack of test data from the ring and handed it to Flitwick.

Flobberworm is a ten-inch long worm, generally brown in color, and likes to stay in a humid environment. They can be seen in the shade of the Forbidden Forest.

Although the mucus of Flobberworms can make magical potions thicker, they are not taken seriously because they are too common, just like catkins. They are one of the food sources for other magical animals in the Forbidden Forest and are at the bottom of the entire food chain.

So Felix has no psychological burden to use Flobberworms for testing without worrying about legal issues. But the results are often not beautiful. The already ugly caterpillars have pustules growing on them, which looks scary.

And the key is that he can't find the problem.

Flitwick sat on a chair with a blue cushion, his feet dangling in the air, he looked through the data and thought carefully: "Could it be related to the imbalance of magic?"

"Imbalance?" Felix asked.

"Yes, I recently reviewed this spell. The Zooming Spell was completed by me with reference to modern magic theory. It can be said that it is a composite spell. Therefore, there may be discontinuity in the magic at the joint."

Felix thought for a while and said, "I have also considered this problem, but I didn't feel anything strange or sluggish during the casting process."

"We can try it!" Flitwick jumped down from the chair, "Each person is responsible for a part of the work, you cast the spell, and I will sense it."

Felix understood what he meant: "You want to use other magic to amplify your senses to feel the formation and flow of the spell? It is indeed worth a try. I don't have the conditions to do this alone."

Flitwick laughed, "Isn't this the meaning of cooperation?"

He pointed his wand at himself and whispered, "Super perception... sharp ears and eyes... magic manifestation... voice of Adimo..." Magic lights flashed on Flitwick.

Felix looked at this scene in admiration. Few people can do this. Just solving the problem of multiple spells affecting each other can stump 99% of wizards.

Soon, Professor Flitwick finished his work. He looked very strange. His ears turned into long, bronze trumpets, his eyes were gray, and his face, which looked like a goblin, was flashing with different colors of light, like a colorful light bulb.

Flitwick's expression was very strange. He struggled to maintain the effect of the spell. He squeezed out a few words from his teeth: "Hurry up... I can't hold on for long..."

Felix's expression was solemn. He deliberately mobilized his magic to make it more active. The light blue light continued to gather, and then burst out a dazzling beam of light.

His spell hit a feather pen, and the feather pen made a "crackling" sound, and quickly expanded and grew larger. From the size of a dagger, it turned into a slightly curved spear in the blink of an eye, and it continued to change.

When the feather pen extended to half of the office, it finally couldn't withstand Felix's magic and exploded with a bang. A huge shock wave spread out.

The whole office was like a hurricane passing through, a mess.

Felix took two steps back under the Armor Charm. Flitwick was blown away because he had to maintain the spell. His small body somersaulted in the air. He quickly pointed his wand at himself and then slowly floated down.

Flitwick was in mid-air, staring at the blue powder that was falling down like a bright blue galaxy. He couldn't help but excitedly said: "Felix, your magic is too strong. It has completely changed the structure of the quill."

After calming down, he warned: "Don't use it on people before this magic is completely perfected."

Felix nodded and said, "I think so too. Filius, did you find anything just now?"

"Oh, it's amazing... I did find something interesting." Flitwick waved his wand, restoring the furnishings in the room to their original state. Then he shook his wand and threw out a bronze smoke.

The smoke was constantly changing, and it turned into an illusion of a wizard casting a spell. Felix recognized that this was the scene of his own casting.

"Here, here, and here, there are extremely subtle imbalances in these three locations." Flitwick used the silhouette condensed from the smoke to explain what he saw.

Felix stared at the screen and said softly, "I didn't notice it before." Flitwick

laughed heartily and said, "It is indeed difficult to find it by one person, but anyway, we have a new idea."

After leaving the office, Felix went to the Potions Professor's office again, discussed the teaching content of the new school year with Snape, and told him about inviting Flitwick.

Snape looked at him suspiciously, "I thought you would invite Lupin."

Felix stared at him without saying anything. Don't you know why?

Maybe his eyes were too direct, which made Snape a little angry. "I have something else to do. If you don't mind, Felix..."

...

In the evening, Felix was sorting out the information of the Magic Club in the office. It was not until Hermione knocked on the door to receive magic training that he realized that he had missed dinner.