Many fanfictions center around Poseidon's role in prophecies. In the Percy Jackson world, prophecies are a big deal. So, in these stories, Poseidon could be trying to manipulate or fulfill prophecies that involve Percy. He might be working with or against other gods to ensure a certain outcome. There are also plots where Poseidon discovers new secrets about Percy's destiny and has to take action to either protect or guide him in a way that wasn't in the original narrative.
The 'enemies - to - friends - to - lovers' plot is also quite common. At first, they might be suspicious of each other because of their different backgrounds. But as they face challenges together, they start to trust and then develop feelings for each other. There are also fanfictions where they are both on a quest to find a powerful artifact that has significance in both their worlds. Along the way, they learn about each other's families and pasts.
Annabeth is often a popular character. She could be in a story where she has to help Percy deal with his relationship with Poseidon. Maybe she gives him advice on how to handle Poseidon's overbearing nature or how to make the best use of the gifts Poseidon gives him.
One popular plot is the accidental encounter. Maybe Harry is on a mission in a place where Percy also happens to be, and a misunderstanding leads to a fight. Another plot could be a competition of sorts. A powerful being decides to test the two heroes and pits them against each other in a battle arena. There's also the plot where the two are forced to fight because of a spell or a curse that makes them see each other as enemies.
One popular plot could be Percy going on a quest to protect something that is dear to Artemis. For example, he might have to safeguard an ancient relic that is crucial for her domain. Another could be Percy having to prove his loyalty to Artemis in the face of opposition from other gods who don't trust his intentions. And sometimes, it's about Percy and Artemis teaming up to face a common enemy that threatens both of them and their worlds.
One common theme is the father - son relationship. Since Percy is Poseidon's son, a lot of fanfictions explore how they interact and support each other.
The allure lies in the fact that Percy already has a very interesting backstory. As the Champion of Poseidon, fanfiction writers can expand on his powers and his place in the mythological world. For instance, he could be sent on quests that are specifically related to Poseidon's domain, like protecting a sacred sea temple from an ancient evil.
One interesting plot could be Percy having to prove himself to Poseidon in a new and unexpected way. For example, he might have to solve a mystery that is directly related to Poseidon's power over the sea but in a realm that is unfamiliar to both of them, like an underwater civilization that has been lost for centuries.
One common theme is family. These fanfictions often explore the father - son relationship between Percy and Poseidon, showing how they grow closer and understand each other better.
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.
One common ability is enhanced water manipulation. Since he's still related to Poseidon, his control over water becomes supercharged. He could do things like create massive tidal waves with just a thought. Another ability is the power to manipulate chaos energy. This might be used to distort reality around him, making it difficult for enemies to attack him directly.