One idea could be a new prophecy that involves the demigods having to travel to an unknown realm to retrieve a powerful artifact before the Titans use it to destroy the world. Another could be a fanfic where the demigods form an alliance with some previously thought - of - as - enemies, like certain monsters who also don't want total chaos. Or perhaps a story where a demigod discovers a hidden power within themselves that has the potential to change the balance of power between the gods and the Titans.
Well, you could have a 'heroes of olympus fanfic' where the demigods get stuck in a time loop. They keep repeating the same day over and over until they figure out how to break the cycle. It could be related to a curse placed by an angry minor god. Another plot could be that the demigods are suddenly swapped with their godly parents' powers and personalities. This would lead to a lot of chaos and humorous situations as they try to deal with their new - found 'godly' selves. And a third idea is a story where the demigods find a secret school for training half - bloods that has been hidden for centuries and has different training methods than Camp Half - Blood.
One idea could be exploring the backstories of minor characters in more depth. For example, you could write about the early life of a demigod who was only briefly mentioned in the original series. Another idea is to create alternate endings to the main story arcs, like what if the heroes had made different choices during a crucial battle? You could also focus on the relationships between the characters in a different light, perhaps showing a friendship that was hinted at but not fully developed.
You could do a story where the characters are swapped into different roles. For example, the usually brave hero becomes a coward and has to learn to overcome his new - found fear. Or perhaps a story where the characters are put in a completely new setting, like a modern - day city instead of their usual mythological landscapes. They'd have to adapt and still use their powers in this strange new environment.
One idea could be that the heroes travel back in time to the founding of Camp Half - Blood and have to deal with the very first demigods. They might face challenges like different rules and more primitive living conditions. Another could be going back to a time when the gods were at war with each other more openly and getting caught in the middle of it. Maybe they travel forward in time and see a future where the demigod world has completely changed, like new alliances between different pantheons.
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.
Well, you could write a fanfic that focuses on the backstories of the characters in 'Blood of Olympus'. Maybe explore how Percy Jackson became the hero he is from a different perspective. Or create a plot where the gods interfere more directly in the demigods' quests in the fanfic. This could add more drama and tension as the demigods have to deal with the gods' complex personalities and motives on top of their existing challenges.
Another interesting concept for 'Heroes of Olympus fan fiction' is to create a new adventure where the characters from different camps, like Camp Half - Blood and Camp Jupiter, have to team up in a completely unexpected setting. Say, they end up in a modern - day city that has been mysteriously cursed, and they need to use their combined powers and knowledge to break the curse.
Maybe there could be a school competition that is secretly being influenced by the gods. The teams in the competition unknowingly have to deal with various magical obstacles and challenges that are related to the mythology. For example, a track race where the track suddenly turns into a river like the Styx, and the runners have to find a way to cross it without getting dragged under.
One idea could be Jason and Percy having to team up for a special quest that no one else can handle. Maybe they have to retrieve a powerful artifact hidden deep in a dangerous realm. They start off not getting along well because of their different leadership styles, but as the quest progresses, they learn to respect each other and combine their powers in unique ways to overcome obstacles.
One idea could be Percy having to deal with a new, powerful enemy that even the Olympians are afraid of. He has to use his unique skills and form new alliances.
A great fanfiction idea is to have the heroes of Olympus time - travel. They could go back to the time of the ancient Greek heroes and interact with them. Maybe Percy meets Theseus and they have to compete in some sort of challenge. Or the story could focus on a character like Nico di Angelo and his journey to discover more about his powers in a place that is off - limits to most demigods, like the Underworld's deepest secrets. There could also be a fanfic where the demigods have to deal with a curse that affects their powers in strange ways.