A possible plot might be that Harry uses his Superman - like powers to help the wizarding world during times of peace as well. For example, he could use his super strength to rebuild parts of Hogwarts that were damaged in previous battles. Or he could use his flight to quickly transport important magical artifacts from one place to another. Also, there could be a plot where the wizarding community is initially afraid of Harry because of his non - magical powers, but he has to prove that he is still one of them and is there to protect them.
In this fanfiction, a plot could involve Harry's journey to understand his Kryptonian heritage. He might travel to the Fortress of Solitude (if it exists in this fanfiction world) to learn more about his father's side. Along the way, he could face challenges from both the wizarding and non - wizarding worlds. There could also be a plot where the Ministry of Magic tries to regulate Harry's superpowers, fearing that he could become too powerful. This would lead to a conflict between Harry and the Ministry, while at the same time he is still fighting against Voldemort and his followers.
There could be a conflict between Harry and the existing wizarding order. The Ministry of Magic might view Harry as a threat because of his connection to Orochimaru. They would be worried that he might bring dark magic into the wizarding world. Harry would then have to fight against the prejudice and suspicion of the wizarding community, while also trying to figure out his own identity and loyalties.
Well, it could be a really wild story. Harry would have superhuman abilities from Superman on top of his wizarding powers. He might be able to fly around Hogwarts using his super speed and strength. And when facing Voldemort, he could use heat vision or super breath in addition to his spells. It would be a whole new level of epic battles.
Hermione would definitely be one of his allies. She is smart and would be able to help him research about his new identity and how to control his powers. For example, she could find ancient texts in the Hogwarts library that relate to both the wizarding world and the Greek gods.
His friends from Hogwarts could still be his allies. Hermione would use her intelligence to help him understand his new situation. Ron would be there for moral support. Additionally, any friends or allies that Rias has in her world could also become Harry's allies. They might be magical creatures or other powerful mages.
Hermione would definitely be an ally. She's smart and would be able to help Harry research about his 'son of Mars' heritage, finding ancient spells or texts that could explain it further.
In this fanfiction, some of the potential allies for Harry could be the magical creatures that have a connection to Norse mythology. For example, the Valkyries. They could help Harry in battles or in understanding his new heritage. Another ally could be Odin, Frigga's husband. Despite the initial shock of Harry's existence, he might see the value in Harry and offer his protection and guidance. And don't forget Neville. He's always been a loyal friend to Harry, and in this new scenario, he would continue to be an ally, perhaps even more important as Harry faces new and different challenges.
One potential ally could be Hagrid. Hagrid has always been a friend to Harry, and in this fanfiction, he could help Harry understand his newfound heritage as the son of Hephaestus. Hagrid's knowledge of magical creatures could also be useful in Harry's adventures related to his Hephaestus - given abilities.
One plot twist could be that Harry's real father was not James Potter but an unknown figure from Hawkgirl's world. This would completely change the dynamics of his family story. Another could be that Voldemort discovers Harry's Hawkgirl heritage and tries to use it against him by creating a spell that combines dark magic with the technology or powers associated with Hawkgirl's world.
Another storyline could involve Harry being trained in both magic and combat skills by Tony. They could team up to fight villains from both the wizarding world and the Marvel universe. Harry could use his magic to counter the superpowers of Marvel villains while Tony provides the technological backup.
Dumbledore could be a powerful ally. He has a deep understanding of magic and would be interested in exploring Harry's new abilities. Also, some of the more open - minded members of the Order of the Phoenix might see the potential in Harry's unique heritage and support him, like Lupin or Sirius if they were still alive in the fanfiction.