Hogwarts: I rely on MC to pretend to be an alchemy professor

[Preface: This chapter contains magic changes with enchantment properties (disappearing curse), which is a secondary creation]

A man in a black robe with an unclear face was kneeling on the ground. In front of him was a unicorn lying on the ground with serious injuries. Silver-white blood flowed from its neck and was licked up by the man in black.

Originally, the two sides should have no intersection. One side originally planned to take the main road and patrol simply.

The other side deliberately chose this uninhabited place. Both sides tacitly did not want to cause trouble.

Until Kaisen decided to go in a straight line, the two sides bumped into each other.

And the man in black also turned around and found Kaisen and several little wizards.

"Spread out, find yourselves in shelters and hide." Kaisen said without hesitation. This time, the man in black was different from Ronan.

Ronan was a native creature of the Forbidden Forest. There was no problem for him to appear there, not to mention that he had no malicious intent.

The guy in front of him who came to the forbidden forest in the middle of the night to kill unicorns and drink their blood was a naked black wizard, and black wizards must use the fastest speed and the most thunderous means to wipe him out.

Three withered skulls exuded ruin and death, howling and rushing towards the black-robed man.

The black-robed man waved his wand and quickly picked up one of them, but the other two were about to rush in, so he had to roll to one side in embarrassment.

Two withered skulls exploded on the ground, and one was picked up and exploded on a towering tree.

At the same time, the places where the two exploded quickly produced visible withering. The soil was fine, but the poor tree almost instantly turned into a structure similar to charcoal.

"In Hogwarts, the famous Professor Kaysen actually knows this kind of black magic?" The man in black said hoarsely.

"If it's to kill a dark wizard like you, I only hate myself for not knowing the killing curse!"

In the corner of the battlefield, the four Gryffindors who were secretly peeking at the screen looked at Professor Kaysen at this moment. He was still gentle as usual, but now his eyes were as cold as Snape looking at Neville's troll test paper, which was ten thousand times more terrifying than that.

Professor Kaysen, who was usually as warm as the sun, disappeared, and was replaced by the cold winter north wind that wanted to kill the dark wizard in front of him all the time.

"Avada Kedavra!"

A pale green spell was shot out from the wand in the hand of the man in black. Seeing this, Kaysen raised his hand and an obsidian wall was formed to block the killing curse.

He waved his hand again, and the wall instantly shattered into sharp pieces of obsidian fragments, shooting towards the man in black.

"Cursed Flame!"

The blood-red fierce fire rose up and swallowed all the obsidian fragments that flew over.

Seeing this, Kaisen snorted coldly, waving his wand and rushing towards the vague figure behind the flame with several ender crystals.

The huge shock wave generated by the crystal explosion made the fire tremble, and the figure flashed with strange light, but was not blown into inorganic matter on the spot, but was holding on to his body and had not fallen down.

"Stay here and wait for death!" The man in black took out a broken glass cup from his pocket, with waves of space fluctuations rolling on it. It was a door key.

The moment the man in black took out the door key, the whole person suddenly disappeared, and the wall of fire in front of him was no longer bound by its owner, and instantly began to devour and spread.

"Professor! Can you use that time on the duel stage!" Hermione shouted with her little head exposed.

"This time the flames are endless, it's a pity that I can't use that!" Kaisen quickly took out paper and pen, and the tip of the feather pen quickly drew various complex symbols on the parchment, and finally he summoned the enchantment table.

"If I catch him, I promise that guy will suffer!" He put the parchment into the magic book floating on the enchantment table. As the magic book turned over, a magnificent purple magic enveloped the fire that covered the sky.

"Disappearing curse!"

Buzz!

As the magic book in Kaisen's hand closed, the fire that covered the sky suddenly disappeared out of thin air. If the trees within a few miles were not burned by the fire, there would be no carbon left. Several young wizards almost thought it was a nightmare.

Boom!

There was another golden-red fire. Kaisen's shaking hands clenched the wand, and his bloodshot eyes looked at the figures walking out of the fire.

Dumbledore, Professor McGonagall, Snape, Filiu...

"Kasen!"

"Professor!"

Harry and Neville, who were always paying attention to Kaisen, quickly climbed over the cover and caught Professor Kaisen who was almost headfirst.

Dumbledore's fearful eyes were filled with undisguised anger, but he calmed down and walked over quickly: "...It's just exhausting self-protection, Severus."

Snape quickly took out two bottles of magic potion from his arms, pushed Harry and Neville aside like picking up trash, then opened the potion stopper and poured it into Kaisen's mouth. He did not forget to help Kaisen raise his chin to avoid choking.

"That damn dark wizard, how dare he...how dare he!" Professor McGonagall looked at the devastated battlefield and Kaisen lying unconscious on the ground with red eyes.

She couldn't imagine, if Kaisen wasn't here, if it was Hagrid who led these little wizards out to patrol the Forbidden Forest today...

She felt suffocated. She just wanted to give the five little wizards who made mistakes a shocking punishment, but...

Professor Flitwick and Professor Sprout were searching with their wands. If the fire had not been completely extinguished, it would be a big trouble.

"Principal Dumbledore, Professor Kaysen..." The other three little wizards also ran over and looked at Dumbledore and asked.

"Severus is an expert in this area."

"...The magic power is overdrawn, but it can be replenished. Just drink two bottles of potion, but the mental power is exhausted... He can't think of going to class within a week." Snape said with a frown.

Dumbledore nodded: "This is the best result. Send him back to the office."

"Don't send him to the medical wing... Oh." Harry said halfway quickly, and suddenly realized that there was another black wizard Quirrell who didn't get along with Professor Kaysen in the medical wing.

If Professor Kaysen were to send him there now, it would be like sending food to Quirrell, so he would rather go to his own office, so he quickly stopped talking.

Dumbledore looked over and nodded in agreement.

"Severus, please brew the potion." Dumbledore said as he gathered everyone together. After a burst of fire, everyone appeared in the alchemy office.

After Dumbledore sent everyone away, only he, Snape, and Kaysen, who was unconscious on the bed, were left in the office.

And now Dumbledore was leaving too.

"Where are you going?" Snape asked.

"I'm going to find the alchemy textbooks from my school days. It seems that I need to be a substitute alchemy professor for a week."

"I don't think it's necessary!"

Someone who was unconscious just now lying on the bed struggled to sit up from the bed.