Well, a frequent plot twist is related to Percy's origin. In some fanfictions, it turns out that his assassin - god powers are not a result of some new blessing but are actually related to his long - lost family heritage. Maybe he has a secret relative who was an assassin - god in the past. Also, there can be a plot twist where the entire concept of the 'God of Assassins' is a ruse created by a more powerful god to manipulate Percy. He might think he's on a path to become this new entity, but in reality, it's all part of a bigger scheme. Another interesting plot twist could be that the mortal world starts to notice Percy's assassin - like activities, and he has to deal with both the godly and mortal consequences.
Often, in these fanfictions, a plot twist can involve Percy's relationships. He might fall in love with someone who is secretly an enemy agent in the assassin world. This would completely change the dynamics of his relationships. Another plot twist could be that his powers as the God of Assassins are tied to a specific weapon or artifact that gets stolen. He then has to embark on a journey not only to retrieve it but also to figure out why it was taken. And sometimes, there's a plot twist where Percy finds out that the rules of being a god in the assassin context are completely different from what he expected, which throws his whole understanding of his new role into chaos.
In some fanfictions, Percy's half - brother Tyson might be made to betray him. This could be due to being tricked by some sea monster that convinces Tyson that Percy is a danger to their kind. Also, Grover could be lured into a situation where he has to choose between saving the wild and betraying Percy. It often makes for a very heart - wrenching story as Grover and Percy have such a strong bond. Sometimes, the betrayal comes from an unexpected source like the gods themselves. They might use Percy as a pawn and then turn on him when he's no longer useful.
Well, in some fanfictions, a great plot twist is that Percy, being born a god, discovers he has a connection to an entirely different pantheon than expected. Maybe he thought he'd be a Greek god like Poseidon, but instead has ties to the Norse gods. Another interesting turn is when his birth as a god is part of a much larger scheme by an ancient and powerful entity. And then there are those where Percy's new godly status causes a rift between him and his mother, as she struggles to accept this new version of her son.
One interesting plot twist could be that Percy discovers he has a long - lost sibling within the family. Maybe a half - brother or sister from a different godly encounter that his parents had in the past. This would change the family dynamics completely and add a new layer of relationships for Percy to navigate.
One unique plot twist could be that Percy has hidden powers from his Titan heritage that no one, not even the gods, expected. For example, he might be able to control time in a small way, which is a power not associated with his normal demigod abilities.
One interesting plot twist could be that the daughter of Nyx has a hidden power that is the key to saving Olympus from a new, unknown threat. Maybe she can control time in a way that no one expected, which throws the whole dynamic between the gods and demigods into chaos.
A great plot twist could be that Percy, as the champion of Artemis, has to deal with the jealousy of other gods. Since Artemis is a powerful and respected goddess, some other gods might not be happy about Percy being her champion. This could lead to various challenges for Percy, such as being framed for a crime he didn't commit by a jealous god. Or perhaps, there could be a twist where the hunters of Artemis have mixed feelings about Percy. Some might see him as an intruder, while others start to develop a different kind of respect for him, which creates internal conflicts within the group of hunters.
One common plot twist is the discovery of a hidden power. For example, the reincarnated character might suddenly find out they have a unique ability related to a minor god that no one expected. Another is a change in the prophecy. Instead of the original prophecy being fulfilled in the expected way, it takes a different turn because of the reincarnated character's presence. And sometimes, there's a betrayal from an unexpected source, like a character who was thought to be a friend turns out to be working for an enemy due to some dark secret from the past.
A possible plot twist could be that Percy's loyalty is tested between the Greek and Shinto gods. Maybe the Shinto gods want him to do something that goes against the Greek gods' wishes, and he has to decide which side to take. Another twist could be that Percy discovers he has a long - lost Shinto sibling who has been working against him all along, thinking he's a threat to their place in the Shinto pantheon.
A great plot twist could be that Naruto is actually a demigod in the Percy Jackson sense all along. Maybe his parents were from the world of Greek gods but were sent to the Naruto universe for some reason. Another twist could be that the God of War, say Kratos, is actually related to one of the main clans in the Naruto world. This would completely change the power dynamics and relationships in the fanfiction.
One idea could be that Percy is framed as an assassin within the demigod world. The other demigods start to hunt him down, but he has to prove his innocence while also uncovering the real assassin's plot. Another could be an alliance between Percy and some assassin - type characters from other mythologies to take on a common enemy that threatens both their worlds. Maybe a powerful titan or a new, dark god.