A great 'Percy Jackson pre Heroes of Olympus' fanfiction could be one that details Percy's dreams and premonitions. Since he is a demigod, he might have had some strange dreams that he didn't fully understand at the time. The fanfiction could explore how these dreams might have been early warnings or signs related to the upcoming events in the 'Heroes of Olympus' series. It could also show how Percy initially dismissed them or was confused by them.
There are fanfictions that delve into Percy's training with Chiron before the 'Heroes of Olympus' series. They might show his struggles and growth as he learns to control his powers better. For example, a fanfic could describe a time when Percy nearly loses control of his water powers during a sparring session and how Chiron helps him regain confidence. Also, some fanfictions might introduce new characters who were part of Percy's pre - 'Heroes of Olympus' life but never made it into the official books.
One interesting fanfiction could be about Percy's early days at Camp Half - Blood before the events of 'Heroes of Olympus'. It might explore his friendships with Grover and Annabeth in more depth, like how they really bonded over their first few quests. Another could focus on Percy's relationship with his mom, Sally, and how she influenced his early understanding of his demigod nature.
Percy Jackson himself is obviously very popular. Fans love to read more about his early adventures and his character development. Annabeth Chase is also a common character in these fanfictions. Her relationship with Percy and her own intelligence and skills are often explored further. Grover is another popular one as he is Percy's best friend. His role as a satyr and his loyalty to Percy are often highlighted in fan - created stories.
A plot where the demigods have to team up with their mortal enemies, like some of the monsters, in order to face a greater threat that endangers both their worlds. This could lead to some really interesting character dynamics and moral dilemmas.
A great fanfiction idea could be Piper having to deal with a situation where her charm - speak backfires. For example, she tries to use it on a powerful enemy, but instead it makes the situation worse. This would lead to her having to find a new way to defeat the enemy, perhaps by relying more on her physical combat skills and strategic thinking, which would be a new and exciting take on her character.
One possible plotline could be Percy being betrayed by the gods and thus deciding to take on Olympus. Maybe he discovers some dark secrets about the gods' rule that make him believe destruction is the only way to bring true justice.
Maybe there's a plot where the demigods are trying to improve the living conditions on Olympus. Since it's a place full of powerful beings, it might be in a bit of chaos. So they could be working on things like building better homes or creating a more organized system for the lesser - known gods.
One idea could be Percy having to face a new, unknown monster that is immune to water. He'd have to rely on his other skills and the help of his friends in a completely different way.
In some 'Percy Jackson Raised on Olympus' fanfictions, there could be a plotline about Percy uncovering long - hidden secrets of Olympus. For example, he might discover a forgotten prophecy that has implications for the entire pantheon. Also, his interactions with the nymphs and other mythical creatures in the Olympian realm can make for an exciting story. Maybe he has to protect them from a new threat that is emerging within the boundaries of Olympus itself.
One interesting fanfiction could be about Jason and Percy teaming up for a super - difficult quest. They might use their unique powers in tandem, like Percy's water - related abilities and Jason's control over the wind. It could involve them facing a new, powerful monster that neither has encountered before.
Percy Jackson himself is always a popular choice. His adventures in the original series have made him a beloved character, and fans love to explore new scenarios for him, like what if he had different powers or faced different challenges.
One possible plot development could be Percy and his friends facing a new, even more powerful enemy. Maybe an ancient primordial being that was previously sealed away has been awakened. For example, a new Titan or a primordial chaos entity. Another development could be Percy exploring his new powers or abilities that he might have gained after the events of Heroes of Olympus. He could be training other demigods as well, passing on his knowledge and skills.