If Harry was raised by unspeakable fanfiction, the whole tone of the story would change. It would likely be darker and more chaotic. His relationships with other characters would be altered, and the overall plot would deviate significantly from the original.
The story would be unrecognizable. His character would be different, and so would his relationships.
The idea of Harry Potter being raised by unspeakable fanfiction is quite a strange one. Firstly, the 'unspeakable' nature of the fanfiction might imply that it contains elements that go against the positive and family - friendly nature of the original series. This could result in Harry having a very different personality. He might be more cynical or have a warped sense of right and wrong. In terms of his magical abilities, he could be taught in a completely different way, which might make his spells and magical knowledge deviate from what we expect. His place in the wizarding community would also be very different. Instead of being seen as the hero who defeated Voldemort, he could be an outcast or a figure of controversy due to his upbringing in this 'unspeakable' fanfiction - created world.
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.
Harry in this fanfiction is likely to be more ruthless. Voldemort's upbringing would make him less empathetic. He may value power above all else and be more willing to use dark magic to achieve his goals. His relationships would also be different. He wouldn't have the same close - knit group of friends as in the original story. Instead, he might be surrounded by Death Eaters or those who follow Voldemort's ideology.
Well, if Harry Potter was raised by Bruce Banner, it would be a very different story. Harry might grow up with a scientific mind. He could learn about gamma radiation and Banner's research. And instead of using magic wands, maybe he'd try to use science to solve problems. Also, he might be more cautious about his anger, like Banner, fearing to turn into something he can't control.
Well, for one thing, Harry would probably be more in touch with the old magic. Merlin has a deep connection to the roots of magic. So Harry might learn spells and techniques that have been long forgotten. His relationship with Hogwarts could also be different. Maybe he would see the school as a place to further expand on what Merlin has already taught him, rather than a place to discover magic for the first time.
Well, this type of fanfiction changes the original story in multiple ways. Firstly, the character of Harry is likely to be more reserved and perhaps more studious under Snape's care. Snape, being a strict teacher, would enforce discipline in Harry's study of magic. Secondly, the whole mystery around Harry's parents and his role in the wizarding world might be revealed to him in a different order. Since Snape has his own secrets and grudges related to James Potter, he might tell Harry things in a different light compared to Dumbledore. Moreover, the relationship between Snape and the other Hogwarts faculty would also change. They would have to accept Snape as Harry's guardian, which could lead to some interesting power dynamics and storylines at Hogwarts.
He becomes more humble. Elves are used to serving and being in a subservient position. Growing up with them, Harry would learn the value of every being, no matter their status. He'd be less likely to show off his magical abilities like he might have in the original story.
He'd be more adaptable. Quarians live in a different way than wizards, so Harry would learn to be flexible in new situations.
His personality would likely be more cold and calculating. He'd be used to getting his way through underhanded means taught by the villains.
He might become more confident in his pure - blood heritage. Since Dorea Black is from an old pure - blood family, she could instill in Harry a sense of pride and belonging that he didn't have in the original story. This could change his attitude towards other pure - bloods and half - bloods.