Well, the main antagonists could be a group of rogue demigods who have formed a cult around Kronos. They believe that Percy, as the heir of Kronos, should lead them in overthrowing the current order of the demigod world. But Percy doesn't want any part of it, so they become his enemies. Another possible antagonist could be an ancient being that was once in league with Kronos and now sees Percy as a means to resurrect Kronos or continue his dark legacy. This being would stop at nothing to force Percy to embrace his role as the heir.
One idea could be Percy having to face moral dilemmas as he discovers more about his connection to Kronos. For example, he might be tempted by the power Kronos once held. Another could be Percy having to deal with the distrust of his friends who fear he'll turn into an heir of Kronos in a bad way. He could also go on a quest to find a way to sever his connection to Kronos if it's a negative one.
In fanfiction, Kronos's role is not just limited to being a villain. Sometimes, he can be a catalyst for character development among the demigods. His actions force the heroes to become stronger, both physically and mentally. For instance, his threat might make Percy Jackson more determined to master his powers. Also, Kronos can be used to introduce new plot elements, like a new weapon or a magical item that has the power to stop him.
One great Kronos fanfiction could be about his backstory before he turned evil. Maybe it explores his relationship with the other Titans and what led him to start the war against the Olympians.
Yes, there are likely fanfictions out there with this concept. Fanfiction writers often explore alternative storylines and relationships. However, it goes against the canon as in the original 'Percy Jackson' series, Percy is the son of Poseidon. But in the world of fanfiction, anything is possible.
In some fanfiction, Percy Jackson might be depicted as a champion of Kronos, but this goes against his character in the original series. In Rick Riordan's official books, Percy is a hero who stands against Kronos and his evil plans.
Kronos in Percy Jackson fanfiction is often depicted as a menacing and powerful villain. He represents the ultimate threat to the demigods. Writers usually emphasize his ancient and malevolent nature, his ability to manipulate time to his advantage, and his insatiable thirst for power. His role in fanfiction can range from being the central antagonist in a time - travel plot to a more shadowy figure pulling the strings behind other villains.
If Kronos were to win in a Percy Jackson fanfiction, it would be a cataclysmic event. Kronos represents the old, chaotic order. His victory would mean the collapse of the current pantheon - based system. The gods' domains would be up for grabs, leading to widespread conflict among the Titans and other powerful beings. Percy and his allies would have failed in their quest to protect the world. The very fabric of the Percy Jackson universe, with its themes of friendship, heroism, and the fight against tyranny, would be shredded. It would be a very different and much darker world than the one we see in the original series.
In most Percy Jackson canon, there is no relation to Thor. However, in fanfiction, anything can be possible. It could be that the author has created a unique crossover where Percy Jackson has some connection to being the heir of Thor, perhaps through some magical or divine intervention that the fanfic writer has dreamed up.
Obviously, Percy is the central character. As the heir of Kronos, he is the focus of the story. His friends like Annabeth are also important characters. Annabeth often serves as Percy's moral compass, trying to keep him from fully succumbing to the dark influence of his new heritage. Grover might also be there, providing his usual support and comical relief.