Who could be the new antagonist in Percy Jackson The Last Hero fanfiction?

It could be a rogue demigod who has a vendetta against Percy. This demigod might have spread the false rumors that led to Percy's banishment in the first place, and now he wants to make sure Percy never returns. He uses his own powers and manipulates other demigods and monsters to achieve his goal.

It could be a corrupted demigod who has turned against his own kind. Maybe he was jealous of Percy's status as the hero and decided to use dark magic to become powerful enough to challenge him.

Maybe a new, evil demigod who is jealous of Percy's status as the last of the seven. This demigod has made a deal with some dark forces and has powers that are a match for Percy's. He or she tries to undermine Percy at every turn and stop him from fulfilling whatever mission is associated with being the last of the seven.

It could be a new Titan that was previously unknown. This Titan could have been in hiding all this time, gathering power and now decides to challenge the gods and Percy.

Perhaps a corrupted god. In Percy's new life, one of the gods could become corrupted by dark magic or some external influence. This god, who was once an ally, now becomes the main threat. He starts to manipulate events behind the scenes, causing chaos among the demigods and mortals. Percy has to figure out how to stop this god without completely destroying the balance between the mortal and divine worlds.

Maybe the main antagonist could be an ancient, forgotten monster that has been awakened by Percy's new life. This monster could have a vendetta against Percy specifically or all demigods in general. It could be a really tough opponent as it has been lurking in the shadows for so long, gathering strength and knowledge. It might have some unique abilities that Percy has never faced before, which would make for an exciting conflict in the fanfiction.

A new Titan could emerge as the main antagonist. Maybe one that was hidden away all this time and now has awakened to seek revenge on the demigods. This Titan could have unique powers that the demigods have never faced before.

It could be a power - hungry Atlantean noble who wants to rule not just Atlantis but also the surface world. He sees Percy as a threat to his plans and tries to stop him at every turn.

A new and powerful demon that has emerged from the darkest corners of the underworld. This demon is bent on using Percy's connection to the overworld to break through the barriers between the two worlds and unleash chaos. It has powers that are different from what Percy has faced before, like the ability to manipulate the very essence of the underworld's environment.

A powerful Amazonian sorceress who has turned against her own kind and is now trying to use dark magic to take over the world. She could see Percy as an obstacle in her path and constantly try to defeat him.