Well, one possibility is that Harry's son has to go on a quest to find a lost magical artifact that is crucial for the safety of the wizarding world. Along the way, he could make new friends from different houses, and they would all work together. His relationship with his family, especially how he interacts with Harry as his father, would also be an important part of the story. For example, Harry could be overprotective, and his son would have to prove himself.
In a Harry Potter has a son fanfiction, the plot could involve the son inheriting his father's magical abilities and facing new threats at Hogwarts. Maybe he discovers a hidden chamber that holds a powerful and dangerous magic. He might also have to deal with the pressure of being Harry Potter's son, with everyone having high expectations of him.
Well, one way could be through a magical accident. Maybe a spell gone wrong during a battle or some kind of experiment that binds their magic in an unexpected way, leading to the creation of a child. It could also be a result of a forced situation by a dark force that wants to see the two rival families united in a very strange way.
In a 'Harry Potter Son of Fire' fanfiction, the plot could involve Harry facing a new dark threat that only his fire - related powers can combat. For instance, there could be a dark wizard who has a fear of fire, and Harry has to master his newfound abilities to defeat this foe. His friends might be initially scared or in awe of his new powers.
Well, it could be about Harry having a different heritage as the son of Leonidas. Maybe he inherits some Spartan - like qualities from Leonidas. For example, he could be super strong and brave in a different way than what we see in the original series. He might use these newfound qualities to face Voldemort, like having a more strategic and fearless approach in battles.
One possible plot could be that Harry's connection to Calypso is a secret at first. As he grows up in the wizarding world, he starts to notice strange things about himself that can't be explained by normal wizarding abilities. Eventually, he discovers his true mother is Calypso. This could lead to a whole new set of adventures as he tries to learn more about his mother's world and how it ties into the wizarding world he already knows. He might even face opposition from those in the wizarding world who fear the unknown power he could possess from his Calypso heritage.
Well, perhaps it could be about Harry Potter having to deal with the dark and complex nature of Klaus within him. Maybe he discovers new magical abilities that come from his 'father' Klaus, and he has to struggle to control them while still being the hero we know from the original Potter stories.
Well, one possibility could be that Harry has Elsa's powers in addition to his wizarding abilities. He might use his ice powers to combat the dark forces at Hogwarts. For example, he could freeze the dementors instead of using a Patronus. Another aspect could be his relationship with the other characters. Maybe Hermione would be fascinated by his new powers and try to study them scientifically, while Ron might be a bit jealous at first but then come to see how useful they are in their adventures.
One possible plot could be that since Harry is the son of Ariel, he might have some unique aquatic abilities. Maybe he can communicate with sea creatures, which could help him in his adventures at Hogwarts. For example, when facing challenges in the Black Lake, his connection to the underwater world gives him an edge.
In a 'Harry Potter son of Ursula' fanfiction, the plot could revolve around Harry trying to figure out how he could be Ursula's son. It might start with some strange events or revelations. He could face a lot of rejection from his friends at Hogwarts as they are suspicious of his new identity. He then has to go on a journey to find out the truth about his origin and clear his name. He might also encounter some new magical creatures or spells along the way.
Well, perhaps Harry could inherit some of Kakashi's ninja skills along with his wizarding abilities. He might use his Sharingan (if he inherits it) to detect magic in a different way or use ninja stealth in the wizarding world. Maybe he would be an outcast in both worlds, not fully fitting into the wizarding society because of his ninja - like traits, and not fully accepted in the ninja world because of his magic.
The plot could involve Harry learning about his connection to Rias. He could be sent on a quest that is related to both his Potter identity and his relation to Rias. For example, he might have to find a magical artifact that is important to both his father's side (the Potter side) and Rias' side. Along the way, he would make new friends and enemies, and his skills as a wizard would be put to the test in different ways than in the original Harry Potter series.