One idea could be that Percy discovers a hidden power within the Staff of Hermes that can open portals to different mythological realms not yet explored in the original series. He could then embark on a journey to these new places, facing new monsters and making unexpected alliances.
Maybe the staff gets stolen by a group of rogue demigods who want to use its power for their own gain. Percy, along with his friends, has to track them down. Along the way, they find out that the staff has a connection to an ancient prophecy that could change the fate of the demigod world. So, it's not just about getting the staff back, but also about preventing the prophecy from being misused.
In the fanfiction, the Staff of Hermes could be malfunctioning. Percy has to figure out how to fix it. He teams up with a heretofore unknown relative of Hermes who has some unique knowledge about the staff. As they work together, they uncover secrets about the creation of the staff and its true purpose, which is far more significant than anyone ever thought.
One plot idea could be that Percy, Apollo, and Hermes have to team up to solve a mystery in the demigod world. Maybe there's a strange new threat that's affecting the powers of the gods and they need to figure out the source. Another could be a sort of race or competition between them where they learn more about each other's strengths and weaknesses.
A powerful Titan who was once an ally of Hermes but now wants the staff for himself. He believes that with the staff, he can regain his former glory and overthrow the Olympians once and for all.
Perhaps the Staff of Fire gets stolen and Percy has to go on a quest to find it. Along the way, he teams up with some new demigods he's never met before. They face various challenges like a maze full of fire - breathing monsters. Percy discovers that the Staff has a hidden power that can only be unlocked by a certain combination of his own powers and those of his new friends.
One plot idea could be that Fem Percy, as a daughter of Poseidon, has some sort of mission that involves Hermes. Maybe she needs to use Hermes' speed and messenger skills to deliver an important message across the realms. Since she is a powerful demigod in her own right, their combined efforts could lead to an adventure full of challenges and discoveries.
One interesting plot twist could be that the Staff of Olympus has a hidden power that no one expected. For example, it might be able to reverse time in a small area, which changes the whole dynamic of a battle. Another could be that a character who was thought to be an enemy turns out to be a key ally in the quest related to the Staff. Maybe they were under a spell or had a secret mission all along.
Well, one possible plot could be that Percy, as the adopted son of Hermes, discovers new powers related to speed and trickery. He might use these powers to outwit the monsters that come after him. Maybe he gets involved in a quest where his Hermes - like abilities are crucial in stealing a powerful artifact from a well - guarded enemy stronghold.
Well, in some fanfictions, Percy as the son of Hermes might get involved in a race against time. For example, he has to stop a group of rogue demigods who are misusing Hermes' speed powers. This could involve him using his wits and new - found abilities as the son of Hermes, like being able to move through shadows or having enhanced communication skills with other beings. He could also form an unlikely alliance with some monsters who are also against the rogues.
One plot idea could be Percy having to team up with Hera to rescue a group of demigods who have been captured by an ancient monster. Hera, despite her usual aloofness, realizes she needs Percy's unique skills.
In some fanfictions, Hermes interacts with Percy as a mentor. He might offer advice on how to deal with other gods or mythical creatures. For example, he could tell Percy the weaknesses of a particular monster. In other stories, he may be more of an enigma, his actions and words being hard to decipher. Sometimes, Hermes and Percy form an alliance, like when they have to face a common threat together.
A plot could be that Sally Jackson plants a lemon tree in her garden that turns out to be a gift from a minor goddess. The lemons from this tree have the power to give those who eat them the ability to see through illusions for a short time. Percy uses these lemons to his advantage when he is on a mission to retrieve a powerful artifact that is guarded by a monster that uses illusions to protect it.