It could be a rogue member of the Hunt. Maybe someone who has a personal vendetta against Percy for some past event or just out of jealousy. This character might be secretly plotting against Percy within the Hunt and is the one who orchestrates the betrayal.
One possible plot development could be Percy feeling extremely hurt and isolated after the betrayal. He might go off on his own to find a way to prove his worth again. Maybe he'll encounter some old enemies who now see him as vulnerable and try to take advantage of his situation.
It could be a jealous friend. Maybe another demigod who is envious of Percy's powers or his popularity among their peers. This friend might see an opportunity to get Percy out of the way and so betrays him.
Well, it depends on how the fanfiction is written. But generally, yes, Percy Jackson can be part of the Hunt fanfiction. Fanfiction allows for a great deal of flexibility. In the context of the Hunt, if it has elements of mythology or a need for a hero - like figure, Percy Jackson would be a great fit. His backstory as a son of Poseidon gives him a rich source of material to draw from. He has faced numerous challenges in his own series, and these experiences can be translated into the Hunt fanfiction. For instance, his knowledge of the mythological world and his combat skills could be used to further the plot in a Hunt fanfiction where he teams up with the Hunt characters to achieve a common goal.
There's a chance that it could be a character from Percy's family. For example, a distant relative who has been corrupted by some dark magic. They might betray Percy for their own gain or because they are being controlled, and this betrayal could lead to Percy being killed.
Well, perhaps Percy is betrayed by his friends or allies who he thought he could trust. This betrayal could be due to jealousy, a misunderstanding, or someone's hidden agenda. As a result, Percy feels so hurt and angry that he decides to join the Hunt. In the Hunt, he might find a new sense of purpose, new friends who understand his pain, and he could start to train hard to become a more powerful fighter. He may also seek revenge against those who betrayed him.
Artemis could be seen as the 'guardian of the hunt' in Percy Jackson fanfiction. As the goddess of the hunt in Greek mythology, she has the power and the authority to oversee everything related to the hunt. She could be the ultimate protector of the hunters and the hunting grounds.
Apollo might be the betrayed god. He could have been tricked by another god into betraying Percy. For example, Apollo might have been promised more power or a higher status among the gods if he turned against Percy. But then he realizes too late that he's been used and that he's actually betrayed someone who could have been an ally.
The gods, especially Zeus. He has always been a bit suspicious of Percy. In fanfiction, he could easily be written as spreading lies about Percy to the other gods and demigods, leading to everyone turning against him. Also, some new characters introduced in fanfiction might be the ones who start the chain of events that lead to Percy's all - around betrayal.
One possible reason for Annabeth to betray Percy in fanfiction could be a misunderstanding. Maybe she was misled by false information about Percy's actions or intentions. For example, if someone spread rumors that Percy was secretly working against the demigods, Annabeth might believe it without getting the full story.