The characters would change a great deal. Harry, for example, might be less of the pure - hearted hero. He could have a more cynical view of the world around him, similar to Brightburn. Hermione might be more distrustful of Harry's new - found darker tendencies. Ron could be more afraid of Harry and his powers, which would strain their friendship.
In a 'harry potter is brightburn fanfiction', characters like Dumbledore would have a different role. He might not be as much of a guiding light for Harry. Instead, he could be more of an enigma, perhaps having his own hidden motives that are not so clearly good. And Voldemort could be even more terrifying, with his dark magic taking on new and more menacing forms inspired by Brightburn's dark elements.
He'd probably be more morally ambiguous. Growing up as Crowley's son, he might not have the same clear - cut sense of right and wrong as the original Harry. He could be more cunning and less hesitant to use underhanded tactics if necessary.
The plot would change a great deal. For one, Harry would be much more powerful physically. So when facing Voldemort, he could use Thor's strength in combat, not just rely on magic. He might be able to take on Death Eaters more easily.
Harry would probably be more attuned to dark magic. His upbringing by Satan would expose him to different forms of magic and he would have a different understanding of power. He might be more ruthless in achieving his goals and less concerned about the consequences for others. For example, in the original series, Harry was always worried about the safety of his friends, but in this fanfiction, he might use his friends as pawns if it served his purpose.
If we consider Harry Potter as a God Slayer in fanfiction, the characters would experience significant changes. Harry himself would have a different aura about him. His confidence would grow exponentially as he realizes the magnitude of his new - found abilities. He would start to question some of the established rules of magic. Hermione would be constantly by his side, trying to analyze and understand the new powers from a theoretical perspective. Ron, on the other hand, would be the one to keep Harry grounded, reminding him of their roots and the importance of friendship. And the villains would be more afraid of Harry, seeing him as a much greater threat than before, which could lead to them forming new alliances or strategies to deal with him.
Harry's character could be consumed by anger and a thirst for revenge in a dark fanfiction. This would make him more aggressive and less empathetic. Luna, however, might use the situation to grow in strength. She could become a sort of moral compass for Harry, but at the same time, she might have to harden herself. Maybe she starts to study dark magic not to use it but to understand it better and find ways to counter it. This would change her from a carefree observer of the magical world to a more proactive defender.
He'd be more adaptable. Quarians live in a different way than wizards, so Harry would learn to be flexible in new situations.
If Harry Potter uses Gaster Blasters in a fanfiction, it could change the very fabric of the magical society. First, the perception of what is possible in magic would change. No longer would wands and incantations be the only means of power. Second, the balance between good and evil could be severely disrupted. Harry's new power could make the fight against Voldemort much easier, but it could also lead to new threats emerging as others might seek to gain the power of the Gaster Blasters. Third, the magical creatures in the wizarding world might react differently to Harry. Some might see him as a new kind of threat, while others might see him as a potential ally in a changing world.
It would change the focus. Instead of just following the main plot of fighting Voldemort, there would be more emphasis on preparation. For example, Harry might spend more time learning about how to protect Hogwarts from all - out destruction rather than just facing Voldemort directly.
In this fanfiction scenario, Harry Potter might change in several ways. His perspective on life and death could shift. Knowing that his brother has some sort of'reborn' aspect could make him question the finality of death more. He could also become more empathetic towards those who have lost loved ones. Emotionally, he might be more stable as he has a family connection now. This new bond could also make him more willing to take risks in the name of protecting his brother, which is a different kind of motivation compared to just fighting Voldemort for the sake of the wizarding world. Additionally, he may develop new magical abilities or skills as a result of the influence of his brother's unique situation.
The Dursleys would likely be out of the picture, or at least not as significant. Instead, Harry might be under the care of some dark wizard or witch in Knockturn Alley. His Hogwarts professors would probably view him with more suspicion. His friends, if he made any at Hogwarts from the more 'good' side, would be initially very wary of him.