In addition to being in charge of the night-pot toilet in the school hospital, the twins also need to work for Professor Sprout's greenhouse, and in order to welcome the new academic year, Professor Sprout has opened a new greenhouse, which is not enough for composting, and the twins also need to be responsible for 'escorting' the fermented manure to its destination safely.

After learning the news, Harry mourned for the twins for three seconds, these jobs are not very heavy work, but they are all dealing with, pee and fart, and that is really what it feels like.... stain stains.

"It's totally worth it!"

"You don't have to comfort us, Harry."

The open-minded twins didn't have a sad face facing a month of confinement, but instead had a smile of excitement on their faces as they left Professor McGonagall's office.

Of course, it wasn't because they had become glorious 'dung pickers', but Hagrid had promised them permission to raise the blue ball, but the bird was badly injured, and although the twins' healing spell barely stopped the bleeding, the broken bones and internal injuries that needed to be recuperated had to be dealt with by professionals.

Professor Sylvanus Celtburn, who is currently the Hogwarts Conservation Wizard Conservation Professor, was willing to help them out, but only if he needed the ball bird to show his face in class and act as a model for the lesson.

After all, Professor Celtburn is very old, and with only one limb intact, he can't catch up with this teleporting ball bird, he has always played various magical creatures through the transformation of the horse-shaped water monster he domesticated, and if he can get a genuine model, he will definitely not let go of the opportunity.

After all, the deformation of the horse-shaped water monster will not shrink the body, and a five-meter-tall ball bird is really a bit of a, which makes people complain.

After saying goodbye to the twins, Harry also went back to the lounge, the afternoon class was about to start, he had to go back to get his textbook, but when he got back to the room, he realized.... Defence Against the Dark Arts doesn't seem to have a serious textbook, just something like extracurricular reading....Dark Arts: From Beginner to Azkaban.

The thin book, which is only a few dozen pages, contains a detailed introduction to some of the 'costs' of common black magic, compared to orthodox magic, black magic usually has a certain increase in the effect of spells, but this extra power requires additional effort.

Every gift is secretly priced, and the price of dark magic is often difficult to detect by the wizard who wields it, and because of this, this subtle change is extremely terrifying.

There were still ten minutes before the Defence Against the Dark Arts class started, but the classroom was already full, and most of the students were very interested in Defence Against the Dark Arts, after all, this course could make people feel some kind of vague excitement just by listening to the name, not to mention, the person who taught this class was named Grindelwald.

Perhaps the little Muggle-born wizard didn't know what the name meant, but no one from a wizarding family didn't know what it meant.

Gellert Grindelwald, the leader of the Witch Party, recognized by the world, the strongest dark wizard in Europe, his fame is on a par with Dumbledore, who has the title of the strongest white wizard, I heard that there was a secret duel between the two decades ago, but due to the long time and the deliberate ambiguity of the two parties, people don't know much about it.

But even these words are enough for people to piece together a powerful and incomparable figure in their minds, even if he casts a dark shadow, he still needs to be feared.

As the hands of the clock pointed to two o'clock in the afternoon, a steady sound of footsteps came from far and near, the door of the classroom was pushed open, and Grindelwald stepped in, his silver-white hair was not as long as Dumbledore's, but trimmed into a neat short hair, which made him look much younger than he actually was, and he was more energetic, without the slightest sense of centenarian aging.

Without further nonsense, Grindelwald, parchment in hand, gave a simple roll call, followed by a short opening sentence.

"I'm Gellert Grindelwald, your Defence Against the Dark Arts professor this year, and I'm going to teach you how to be a good soldier and a warrior in the right way after Hogwarts' terrible teamwork last year."

"Now, can anyone tell me what the nature of Defence Against the Dark Arts, the Dark Arts we have to deal with?"

Grindelwald's eyes swept over the classroom, and he didn't see anyone raising their hand.

"Where is the Ravenclaw wisdom of thinking? Is Hufflepuff really a gathering place for a bunch of mediocrities? ”

The corners of his mouth tugged at a hint of sneer, slight but provocative, "In the morning, both Gryffindor and Slytherin had answered my questions, and I think you should be in step with each other and feel free to speak boldly, even if it's a wrong answer." ”

At this point, someone raised their hand, and a child's emotions were easy to provoke, what Gryffindor and Slytherin could do, Ravenclaw and Hufflepuff couldn't do?

"Very well, Miss Granger, please."

Grindelwald nodded her chin slightly, and a somewhat nervous Hermione stood up, her fingers still clutching the corner of the thin book.

"The book doesn't say what black magic is... But I think. Hermione swallowed nervously, answering this kind of question that was not described in the textbook, "I think... Dark magic is an evil force that can distort the mind and take wizards to extremes until they are destroyed. ”

"The most terrible thing is that the erosion of black magic on wizards is very difficult for the user himself to detect, so black magic has become a taboo in the wizarding world and needs to be forbidden."

"Looks like Miss Granger has read your book very carefully." Grindelwald nodded slightly, "Are there any other different opinions?" ”

Most of the young wizards shook their heads slightly, and in their minds, the appearance of black magic was about the same as Hermione's description.

"Looks like Hufflepucciri has a new idea, Mr. Potter, is there anything you'd like to say?"

When he looked at Harry, Grindelwald had a different look in his eyes, after all, this boy who was immortal, he had also heard a little, Voldemort had caused a lot of trouble for Albus after all, even if this guy was a little deflated in Grindelwald's cognition, but he could disgust Albus, he also had a lot of means.

"I don't think the essence of black magic is simply evil, in my opinion, magic is an exchange, so there is a hidden limit to conventional magic, and the amount of magic paid determines the power of magic, but this exchange has some kind of upper limit."

"And the dark magic breaks the upper limit of conventional magic, and the use of black magic is not just about magic, but also about some additional cost, and I think it's probably some kind of human nature, or something fundamental that I don't know, maybe the soul? This leads to the manifestation of black magic, which can influence wizards to fall into the appearance of evil. ”

"Interesting answer." A smile appeared on Grindelwald's lips, "Sit down, Mr. Potter, your answer is a little closer to the truth." ”

Grindelwald pressed his hand, "Then let me tell you the real answer." ”

"In the current wizarding world, the perception of black magic is biased and wrong, limited by this wrong framework, you don't understand what real black magic is!"

"Does it affect the mind? Does it make people wicked and depraved? ”

"The root cause of this is simply that people don't have a proper understanding of black magic."

"All wizards have a wrong understanding of it, even putting the cart before the horse."

"Dark magic itself is not evil, I admit that it has certain dangers, but dark magic is controllable, and Mr. Potter's guess is correct, when black magic is used, there is indeed a certain price, and this price actually exists in other magic that we don't think is black magic."

"Magic, emotions, will."

"These three untouchable but real forces are the foundation of all magic, magic is the basis of magic spells, it is energy, the energy that determines the power of the foundation of magic, and emotion and will are amplifiers, when the magic used is equal, emotions and will will ultimately determine the strength of a magic."

"Compared to what we know about white magic, black magic can use emotions...."

"Which is simpler, protection or destruction?"

Grindelwald confronted the students with new questions.

"It would be easier to destroy." The students' sparse answers seemed a little reserved.

"It seems that everybody has a clear and correct understanding of this." Even if it was just a trivial affirmation, but when it came out of Grindelwald's mouth, it made the little wizards' hearts feel a little uplifted.

"The emotions used in white magic are biased towards the positive, without exception, even if it is used for confrontation, the emotions contained in it are similar to the rather mild ones of repression, such as the disarming spell and the stun spell, but these positive emotions have their upper limit visible to the naked eye."

"It's not that magic has a ceiling, but that there is an emotional ceiling that amplifies the power of magic, although it can be compensated for by a strong will, but a short board is a short board, and a strong will is not something that everyone can have."

"In black magic, destruction is always simpler than protection, compared to mild and stable positive emotions, anger, killing, pain, etc., which represent negative emotions.... We should all know how powerful the power of revenge is, and the anger of revenge will not be a positive emotion that makes everyone happy. ”

"But are all of these negative emotions that drive the dark arts really supposed to be discarded, or are they all evil?"

"It's the same guard, if killing one person can save tens of thousands of people, is such a killing evil?"

"This kind of killing intent is strong, but this kind of killing intent is also positive."

"There is a limit to the protection of protection, and killing for the sake of protection has power beyond the limits of the former."

Grindelwald pulled his wand out of his bosom, it was a Browning M1935 semi-automatic pistol, which was as beautiful as a work of art, smooth and tough, and compared to Professor McGonagall's collector's UPS, this gun was as luxurious as a weapon, like brass and gold, dazzling and dazzling.

"In the Defence Against the Dark Arts class, practice leads to true knowledge, and all empty talk is in the air."

"I just said so much, but it's not as intuitive as what I saw with my own eyes."

"Now, then."

Grindelwald smiled and threw out a black cloth bag, from which a cloud of black mist rose and then coalesced into a terrifying monster floating in mid-air in tattered black robes.

Less than five feet in front of the young wizard, the Dementor from Azkaban unleashed an aura of despair that terrified all living beings, but it seemed that his power was limited by some kind of magic, and the power released by the Dementors who could not escape in place was also weakened.

The screaming little wizards seemed to have been splashed on the head by a basin of ice water, but the despair of being sucked into happiness did not appear in them.

"Fresh Dementors from Azkaban, I think you should be able to impress with such fears."

Grindelwald raised the muzzle of his gun and said in a clear voice that everyone could hear, "Divine Guard." ”

A flash of white light burst from the muzzle of the gun, and a lifelike pale golden phoenix flew out of the muzzle, and this guardian magic called by the emotions of hope, joy, happiness, etc., is the absolute enemy of the Dementors who spread despair and death.

The materialized Patronus has the ability to kill this semi-ghostly dark magic lifeform, and the moment the Phoenix Patronus appeared, the Dementor screamed and began to melt, and the cold despair that enveloped the entire classroom also disappeared with the wind the moment the pale golden Patronus appeared.

A warm force calmed the young wizards, who stared at the front with fear and curiosity, but some small cheers rang out after seeing the Dementors smashed into black mist by the phoenix and disappear completely.

"That's pure protection."

Grindelwald commanded the Patronus to crouch on the podium, "If you look closely, after killing the Dementors completely, the power of the Patronus itself has been weakened a little. ”

Although the little wizards couldn't tell the difference at all, Grindelwald wouldn't lie to them, everyone nodded, and the professor was right.

"The protection for protection is passive, this is the limitation of the so-called white magic, it is not so much that the Patronus killed the Dementor, but that the Patronus cut off a part of his own body and neutralized the energy of the Dementor."

"It's not a killing, it's a respectable and stupid sacrifice."

"What if it's black magic?"

Grindelwald smiled meaningfully, another black cloth bag was thrown out, and a new Dementor appeared in front of the students, but with the previous fright, the curiosity in their hearts was stronger than before, and there were a few exclamations, but no one screamed.

The muzzle of his gun was raised again, pointed at the Dementor once more, and once again uttered the unchanged incantation: "Calling the Gods Guard!" ”

But this time, instead of a white mist with a faint golden light, a terrifying black light as black as an abyss, making people feel uncomfortable.

If the Dementors bring people the despair of depriving people of happiness, then the black light that quickly coalesces into a dark phoenix is constantly radiating killing, death, and fear.

Completely different from the orthodox Patronus, the extreme negative emotions condensed into a Patronus countless times more terrifying than the Dementors, a pure black phoenix, and a Patronus that seemed to have nothing to do with the Guardian.

"Killing for protection, it's justice."

The moment the words fell, the black phoenix flapped its wings and flew, and the pitch-black claws grabbed the dementor's shoulder in an instant, and then tore in half.

Countless black qi exploded, and the power of despair scattered and fled, but after a few pecks from the black phoenix, it was completely devoured and absorbed.

"There is no such thing as good and evil in magic, they are just tools of wizards, if you are scratched by a sharp blade, it means that you are not using it correctly, what we need to do is not to seal this hurtful blade, but to learn the way to wield it correctly."

"Defence Against the Dark Arts, we don't learn how to deal with it, we learn how to control it properly."

"If power is not used, then its existence is meaningless, and in this day and age."

Grindelwald looked at the students with a cold expression.

"We need someone to step into the darkness and guard the light for more people."

"Time is running out, boys." Grindelwald narrowed his eyes slightly and said in a very soft voice.