One possibility is that Harry would have superhuman strength and speed like a Saiyan. He could use his new powers to defeat Voldemort more easily. For example, in a battle, he could move so fast that Voldemort's spells can't touch him, and his powerful punches could break through dark magic defenses.
Well, it could be that Harry discovers he has Saiyan blood somehow. Maybe he starts to show Saiyan powers like super strength and the ability to transform. He could use his Saiyan powers to fight Voldemort in a whole new way, like going Super Saiyan and blasting him with energy attacks that are far more powerful than any magic spell.
It would be really interesting. Harry would have Saiyan abilities. He could fly without a broom, and his hair might turn golden when he powers up. His magical abilities could be enhanced by his Saiyan strength. He could use his ki energy to perform spells in a more powerful way.
One possibility is that the Sorting Hat would have to take into account a new factor - Saiyan nature. Would a Saiyan - like student be better in Gryffindor for their bravery, or in Ravenclaw for their potential to learn about new powers? Another thing that could happen is that the Triwizard Tournament would be even more dangerous. A Saiyan - powered champion could cause destruction on a much larger scale during the tasks. And Dumbledore would have to find a way to control and guide this new power within the school.
Well, it could be really interesting. Harry might have Saiyan powers like super strength and the ability to transform into a Super Saiyan. He could use his Saiyan rage in battles against Voldemort. For example, when facing a Dementor, instead of using a Patronus charm, he might power up like a Saiyan and blast it away with his energy.
Well, it could be about Naruto having the powers of both Saiyan and Kryptonian. Maybe he can use Saiyan's ability to transform into a Super Saiyan and combine it with Kryptonian super strength, heat vision, etc. He could use these combined powers to protect the Hidden Leaf Village from a new kind of threat that no one in the Naruto universe has ever faced before.
Well, it could be really interesting. Maybe the character with Harry Potter and Kryptonian heritage would have some amazing powers. They might be able to use magic like in the wizarding world and also have super - strength or flight from the Kryptonian side. They could use their powers to protect Hogwarts from some new and powerful dark force that normal wizards couldn't handle alone.
One possible plot could be that a half - human half - horse character helps Harry Potter find a hidden magical artifact. The half - horse's speed and knowledge of the Forbidden Forest could be key elements in this adventure.
In some fanfictions, it could be an original character created by the author. Maybe a witch who was the result of an affair that his father had before he married his mother. However, this is completely against the canon of the original books, but in the world of fanfiction, anything is possible.
Well, perhaps the plot could involve Harry struggling with his new - found half - demon nature. He might have to hide it from his friends at Hogwarts for fear of being ostracized. And he could discover that his demon side gives him some unique magical abilities that are both a curse and a gift.
One possible plot could be that Harry discovers his half - demon heritage as he grows older. He might face discrimination from some in the wizarding world who fear his demon side. He then has to go on a journey to learn about his demon heritage and how to control the powers that come with it, all while still fighting against Voldemort or other threats in the wizarding world.