One potential consequence could be a change in his relationships. His friends might be worried or even turn against him. For example, Hermione, who is always concerned about following the rules and doing what's right, would likely be very troubled. Another consequence could be a shift in his own moral compass. The dark arts are often associated with negative and unethical actions, so he could start to make more morally ambiguous decisions.
He might face opposition from the wizarding community at large. The use of dark arts is generally frowned upon in the wizarding world. So, if Harry is known to be learning them, he could be ostracized or even face some form of punishment. Also, it could attract the wrong kind of attention, like from dark wizards who might see him as either a potential ally or a threat to be eliminated.
One possible consequence could be that he loses the trust of his friends. Ron and Hermione, who are firmly against the dark arts, might turn their backs on him. Another consequence could be that he is ostracized by the wizarding community. The Hogwarts faculty, who have always been on the side of good, would likely be very disappointed and may even try to stop him. And he could also attract the attention of the wrong kind of wizards, those who are into the dark arts themselves and might use him for their own purposes.
Bellatrix Lestrange could be a potential focus as a dark arts master in fanfiction. She already has a deep knowledge of the dark arts in the original series. Fanfiction could explore her even more, perhaps showing her training others in the dark arts in a more in - depth way.
There could be various consequences. Firstly, a cease - and - desist order might be issued, forcing the seller to stop selling the fanfiction immediately. Secondly, the seller may have to pay damages. Since 'Harry Potter' is a very valuable brand, the damages could be substantial. And thirdly, in some cases, there could be criminal charges if the infringement is severe enough, although this is less common in cases of fanfiction sales.
He could lose the trust of his friends. In the original series, his friends rely on him to be a force for good. If he starts using the Dark Arts, they would be horrified and might distance themselves from him. Also, he could be in danger of being corrupted by the dark power, which could change his personality and make him more like the villains he once fought against.
There could be a dark arts teacher who is actually a double - agent. This character might seem to be teaching Harry the wrong things at first but is actually guiding him to use the Dark Arts for good. Another new character could be a mysterious figure from an ancient dark arts cult who tries to recruit Harry for their own purposes.
One potential consequence could be disrupting the natural balance of water - based magic. If he teleports too often or without proper control, it might cause ripples in the magical ecosystem of water bodies. Another consequence could be attracting unwanted attention from water - dwelling magical creatures. They might see his teleportation as an intrusion or a threat.
The wizarding economy would be in chaos. Gringotts is the central bank of the wizarding world. Its destruction would mean that people's savings, vaults, and all the financial transactions would be disrupted. Wizards and witches would lose their trust in the financial system.
It can create a lot of conflict. For instance, it might set him against the Hogwarts faculty who are against the use of dark arts. This would add a new layer of struggle to the story.
One potential consequence could be a negative impact on the original 'Harry Potter' brand image. If the fanfic contains disturbing or inappropriate content, it might turn some fans away from the overall franchise. Another consequence could be the spread of harmful ideas within the fan community. For example, if it promotes toxic relationships or unethical behavior, it could influence younger or more impressionable fans in a bad way.
If Harry summons demons in fanfiction, he could face immediate danger. Demons are often depicted as malevolent entities. They might attack Harry instead of doing his bidding. He could also lose control of the situation, leading to chaos around him. His friends might turn against him when they discover what he's done, seeing it as a step into the dark side of magic.