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.
One idea could be Percy accidentally travels back in time and encounters Chronos in his prime. Maybe he has to team up with some of the old - time demigods to stop Chronos from an early attempt at world domination. It would be full of action and adventure as Percy tries to use his modern skills in an ancient world.
One great 'Time Travel Percy Jackson Fanfiction' is 'The Time - Traveling Demigod'. It has an exciting plot where Percy is sent back in time and has to deal with all kinds of challenges that change his understanding of his own world. The author does a great job of keeping Percy's character consistent while also showing how he grows through these new experiences.
One great 'Percy Jackson Time Travel Fanfiction' is 'Time Warped'. It takes Percy back to ancient Greece and he has to deal with all kinds of challenges that are different from his modern - day ones. He meets his ancient relatives and has to figure out how to get back to his own time without changing history too much.
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.
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.
Another aspect could be that Percy is betrayed by a family member. For example, if it is revealed that a relative he trusted was working for an enemy all along. This would shatter Percy's world as family has always been important to him, and it would be a major plot point in the fanfiction, leading to his emotional and physical struggles.
In many Percy Jackson fanfictions, time travel often works through magical artifacts. For example, a special time - turning hourglass might be used. It could be a powerful object left behind by an ancient god or goddess.
To write a great 'Percy Jackson Time Travel Fanfiction', think about the consequences of time travel. If Percy changes something in the past, how will it affect the present and future? You can also add some unique twists. For instance, what if the time - travel device malfunctions and he keeps bouncing between different time periods? And don't forget to include the humor and adventure that are typical of the Percy Jackson series.
The gods are always a possibility. Zeus, for example, has been distrustful of Percy in the past. If Zeus feels that Percy is getting too powerful or is a threat to his rule, he could engineer a situation where Percy is betrayed. He might use other demigods or even mortals to turn against Percy.