First, you need to understand the characters well. For Percy, think about his loyalty and his powers. Zoe is a complex character, so consider her backstory and her relationship with the Hunt. For Chaos, you can be creative as it's a more mysterious entity. Then, come up with an interesting plot, like a new threat that requires all three to work together.
One great 'Percy Jackson, Zoe and Chaos' fanfic could be one where Zoe is sent on a special mission by Chaos. In this fanfic, Percy might get involved accidentally and they have to work together to overcome challenges. For example, they could face new and powerful monsters that are a threat to both the mortal and demigod worlds.
One key element is the relationship between Percy and Zoe. It's often explored in different ways, like from being strangers to friends or even more. Another element is the chaos aspect. It could be a chaotic magic, a chaotic situation they are in, like a world turned upside down by some chaotic force.
Another possibility is a time - travel fanfic. Percy and Zoe get sent back in time to an era when the gods were more directly involved in mortal affairs. They have to figure out how to get back to their own time while also dealing with the chaos of that ancient time period. Along the way, they might even change some historical events that have an impact on the present day in the Percy Jackson universe.
In many Percy Jackson fanfics about the Trials of Chaos, the author might introduce new magical elements or creatures. For example, there could be a chaos - inspired beast that has the power to disrupt the very fabric of the demigod world. The trials themselves might be set in unknown and uncharted places, like a dimension filled with swirling chaos energy. This makes for an exciting read as it takes the familiar Percy Jackson universe and twists it into something new and unpredictable.
One popular Percy Zoe Chaos fanfic is 'The Chaos of Percy and Zoe's Adventure'. It has an interesting plot where they face various challenges together and their relationship develops in unexpected ways.
Their relationship could develop through shared experiences in Chaos's realm. For example, they could start off as reluctant allies, but as they face more and more difficult challenges together, they begin to trust and respect each other more. Eventually, they could become close friends who would die for each other.
One plot idea could be that Percy and Zoe are sent on a mission by Chaos. They have to retrieve a powerful artifact that was lost in a dimension full of dangerous creatures. Another could be that they are reunited in Chaos's realm after their deaths in the normal world and are given a second chance to protect the world from a new threat. Maybe they have to form an alliance with some unlikely allies from different mythologies within the chaos - inspired setting.
The plot could be centered around a prophecy that involves both Percy and Zoe. They are forced to team up despite their initial differences. For example, Percy is more impulsive and Zoe is more reserved. As they journey to fulfill the prophecy, they encounter mythical creatures and ancient magic that test their limits.
Obviously, Percy Jackson is one of the main characters. He is usually at the center of the action. Another common character is Annabeth Chase. Her relationship with Percy often plays a role in the fanfic. Chaos itself can also be considered a main character in a sense, as it is the driving force behind many of the events.