Well, perhaps in the fanfiction, the dragon rider is betrayed when they are blamed for a crime they didn't commit. Maybe it was a theft of a powerful magical item. The real culprit sets up the dragon rider, and Percy, believing the false evidence, turns his back on the rider. The rider then discovers the real thief's identity and has to fight against both the false accusations and the real villain to clear their name and reconcile with Percy.
In this fanfiction, it could be that the dragon rider is betrayed due to a misunderstanding. There might be a prophecy that is misinterpreted. The dragon rider is thought to be the one who will bring doom according to the wrong interpretation. Percy, being influenced by the general belief in this misinterpreted prophecy, distances himself from the rider. The rider then has to find a way to prove that the prophecy has been misread and that they are actually an ally, not a threat.
Another possibility is that it could be a character who has been corrupted by dark magic. This character was once a friend or at least an acquaintance of the dragon rider. But the dark magic makes them see the dragon rider as a target. They betray the rider in the hopes of getting some sort of power or reward from a more powerful evil entity.
One possible plot could be that Percy, with his natural heroic instincts, discovers a hidden world of dragon riders. Maybe he stumbles upon a dragon egg during one of his quests. Since he has a connection with water and dragons are often associated with elements, he could find a way to bond with the newly hatched dragon. This would lead him to learn the ways of the dragon riders, facing challenges from those who oppose a half - blood like him becoming a rider.
One possible plot could be that Percy Jackson, in a crossover world, is somehow made to believe that the Twilight characters are a threat to his world. Maybe he's deceived by some dark force into thinking they're planning to take over Camp Half - Blood. So he betrays them by leading an attack on their territory in Forks, not realizing he's been tricked.
One possible plot for this fanfiction could be that Percy is betrayed by a new character introduced in the fan - made story. This new character pretends to be his friend, gains his trust, and then reveals their true evil intentions. They lead Percy into a trap set by some ancient and deadly enemies. Percy, caught off - guard, is then killed. This would add an element of mystery and new drama to the familiar Percy Jackson universe.
One possible plot could be that Percy is betrayed by one of his closest friends in Camp Half - Blood. Maybe Annabeth turns on him out of jealousy over his growing powers or a misunderstanding. Percy, feeling deeply hurt, decides to disappear into the mortal world. He cuts off all ties with the demigod community and tries to live a normal life, but his past keeps haunting him as monsters still sense his presence.
Well, it could be about Percy finding out that a god he trusted has betrayed him. Maybe this god has been using Percy for their own gain all along, like in battles against other gods or monsters. Percy would then have to deal with the shock and figure out how to either get revenge or make things right in the world of the gods.
It depends. Some Percy Jackson fans might be really into this kind of fanfiction as it combines two exciting elements - Percy Jackson and dragon riding. However, compared to the more mainstream Percy Jackson stories, it may not be as widely known. There are a lot of different fanfiction out there, and popularity can vary greatly depending on the specific fan community and how well it's promoted among Percy Jackson enthusiasts.
One unique plot idea could be that Percy discovers he has a special connection to the dragons because of his demigod powers. Maybe he can communicate with them on a deeper level than others. Another idea is that the dragons are the key to solving a new threat to the demigod world, like a powerful ancient evil that only the combined strength of the demigods and the dragons can defeat.
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.
Well, it could be that Percy is tricked into believing the son of chaos is a threat when he's actually not. Maybe some other characters manipulate Percy's perception with false evidence.