Perhaps Moody, being a very experienced Auror, trains Harry in some dark magic defense techniques that are not taught at Hogwarts. This gives Harry an edge in fighting the dark forces but also makes the Hogwarts faculty a bit wary of him. He could then be in a situation where he has to prove that his knowledge is for good and not for dark purposes.
A possible plot twist is that Moody, because of his past traumas and experiences, has a different view of Voldemort. He might believe that Voldemort can be redeemed or that there are more complex reasons behind his actions. This would put Harry in a moral dilemma as he has always seen Voldemort as pure evil. Harry would have to decide whether to follow Moody's view or stick to his own beliefs in his fight against the Dark Lord.
I really like the fanfiction 'In Moody's Shoes'. It takes the reader on a journey through Moody's eyes. You get to experience his paranoia, his skills as a wizard, and his complex relationship with the Order of the Phoenix. It adds a lot of depth to his character and is a great exploration for any 'Harry Potter' fan interested in Mad - Eye Moody.
In these fanfictions, a really cool plot twist could be that Moody, because of his experience with the dark arts, has knowledge of a secret power within Harry that even Voldemort doesn't know about. He nurtures this power in Harry, which makes Harry a completely different kind of threat to the dark forces. Maybe it's a power related to the ancient magic of the founders of Hogwarts that was passed down in a way no one expected.
Harry would likely be more gruff and less trusting. Growing up with Moody, who was always on guard, Harry would have learned to be more cynical. He might not be as quick to make friends as he was in the original story.
The mystery surrounding Mad - Eye Moody makes fanfiction appealing. In the original series, he had a lot of secrets. Fanfiction allows us to explore those secrets further. For example, we can imagine what he was really thinking when he was teaching at Hogwarts.
Perhaps a plot twist could be that the magical creatures interact with Harry differently. In the original, they had a certain way of relating to him, but in this fanfiction, being raised as a black wizard might make some creatures more or less friendly towards him. Some might see him as a symbol of change in the wizarding world and be more drawn to him, while others might be suspicious. Also, the way Harry approaches magic could be different. He might draw on cultural magic that is unique to his black heritage, which could give him an edge in certain situations or make him a target for those who fear change.
Maybe Harry would have a different view on the wizarding world. Growing up with the Delacours, he'd be exposed to a more international magical community from a young age. So, instead of being so focused on the British wizarding world's problems like Voldemort, he might be more interested in international magical relations and how to unite different magical cultures.
Well, a really interesting plot twist could be his relationship with the other Hogwarts houses. He might not have the same automatic connection with Gryffindor. Instead, he could be more inclined towards Slytherin values, which would completely change his dynamic with Ron and Hermione. Maybe he would form closer friendships with Slytherin students right from the start. Also, his views on pure - blood supremacy could be more complex as he is raised in a family that might have some traditional views on blood purity.
Well, perhaps the nuns are in cahoots with some magical creatures. They could be working with a group of centaurs who have prophesied that Harry must be raised in seclusion among the nuns to gain a certain kind of purity of spirit. Then, when Harry finally enters the wizarding world, he has an aura about him that both attracts and confounds the dark forces. He might also have a special connection to the magical animals due to his time with the nuns, like being able to communicate with them on a deeper level, which would be really useful in his battles against the dark side.
A really interesting plot twist could be that the phoenix, being a symbol of rebirth, has the ability to make Harry remember his past lives. This would give him an edge as he could draw on the knowledge and skills from his previous existences. He might remember spells and strategies that were long forgotten, which would completely change the course of his fight against the dark forces.
One possible plot twist could be that Harry has unique magical abilities related to the ocean. For example, he might be able to communicate with sea creatures, which could help him in his adventures. Maybe he discovers a hidden underwater wizarding community that has been isolated from the rest of the wizarding world for centuries. Another twist could be that his enemies, like Voldemort, have a hard time reaching him in the ocean, but they find a way to use the ocean's power against him in some unexpected manner.