Yes, there are many great ones. You can start by looking on fanfiction websites like Archive of Our Own. Some focus on Percy's new adventures that draw on his unique heritage as the son of both Poseidon and Neptune, exploring how he might handle different mythological challenges.
One common theme is identity. Percy has to figure out how his dual parentage affects who he is. Another is power. Since he has two powerful godly parents, his abilities are often explored in different ways in fanfiction.
Power struggles are also a common theme. In 'Percy the Son of Neptune fanfiction', there are often new threats or power - hungry villains that Percy has to deal with. This creates a lot of action - packed scenes. Additionally, the theme of loyalty is frequently explored. Percy's loyalty to his friends, family, and the gods is tested in different ways in these stories. For example, he might have to choose between following the gods' orders and doing what he believes is right for his friends.
There's a fanfiction called 'Percy's Hidden Powers in Son of Neptune'. In this one, Percy discovers new powers that are unique to the events in 'Son of Neptune'. The author does a great job of tying it in with the existing mythology and the plot of the original story. It's full of action and some really cool fight scenes.
There's also a fanfic called 'Poseidon's Promise'. In this one, Percy has to deal with a mysterious prophecy related to his father. The story is full of twists and turns. It delves deeper into the relationship between Percy and Poseidon, which is really interesting to read about. It also has some great action scenes with Percy using his water - based powers.
One idea could be Percy feeling betrayed by Poseidon and then finding a new family among other outcasts in the demigod world. He could form a group with them and go on adventures that are not related to Poseidon at all.
In fanfiction, their relationship could be developed by having Poseidon be more involved in Percy's daily life. Instead of just popping in during big events, he could be there for the small things too. For instance, helping Percy with his schoolwork that involves marine biology. They could also have a project together like building a new safe haven for sea nymphs. Through this, they would bond over creating something positive. Also, Percy could start to take on some of Poseidon's responsibilities in the ocean, with Poseidon guiding him. This would not only strengthen their bond but also show Percy growing into his role as Poseidon's son.
Well, a great plot for Percy son of Neptune fanfiction could involve Percy getting lost in a time - warp within the ocean. He could end up in an era where Neptune was just starting to gain his powers. This would force Percy to interact with a younger version of his father and also deal with the different rules and threats that existed back then. Additionally, Percy could find a way to bring some knowledge from that time to his present to help in a current conflict. Also, Percy might have to team up with some primitive sea creatures who have their own unique abilities and motives.
In Percy son of Neptune fanfiction, including Nico di Angelo would be interesting. His connection to the underworld could bring a new dimension to the story, especially when dealing with any threats or mysteries that involve both the sea and the underworld. Reyna could also be a great addition. Her leadership skills and combat abilities would make her a valuable ally or a formidable opponent, depending on the plot. And of course, Chiron, the centaur, who could offer his wisdom and guidance to Percy from afar, as he has so much knowledge about the demigod world.
One possible plot idea could be Percy reading it and getting new insights into the story, which then helps him in his own adventures. For example, he might find a hidden clue in the fanfiction that relates to his real - life challenges.