A plot could involve a prophecy that only they can fulfill together. Percy, Jason and Nico are brought together by this prophecy. At first, they don't get along well because of their different backgrounds and ways of doing things. But as they start to explore what the prophecy means and face the initial challenges related to it, they realize they need to work as a team. They then travel to a lost city full of traps and puzzles where they must use their combined skills to progress and ultimately figure out how to fulfill the prophecy.
One possible plot could be that they have to team up to stop an ancient evil that is rising. Each of them brings their own unique powers to the table. Percy with his control over water, Jason with his power over the wind and lightning, and Nico with his ability to manipulate the shadows. They journey to different realms to find the artifacts needed to defeat this evil.
Well, perhaps there is a powerful magic that has been stolen and scattered across different mythical locations. Percy, Jason and Nico are called upon to retrieve the pieces. Along the way, they encounter various mythical creatures and other obstacles. Their team - up is not easy as they have different approaches to problems. However, as they face each encounter, they learn from each other and gradually form a more effective team. They also discover secrets about their own powers and the history of their world during this quest.
One possible plot could be that they discover they are brothers through a series of magical events. For example, a powerful oracle reveals the truth. Then they have to deal with the shock of this new relationship while also facing their common enemies. They might train together to combine their unique powers and protect their world from threats.
It could be about their unique upbringing on Olympus. Maybe they have to deal with the politics among the gods while growing up. For example, Percy might struggle with Poseidon's expectations and his own identity in this divine setting. Jason could be learning about his Roman heritage in a more Greek - influenced environment. And Nico might be trying to find his place among the living and the dead while being raised on Olympus.
In this fanfiction, it could be that Percy, Nico and Jason are chosen by Chaos for a special mission. Chaos might have seen something unique in them, like Percy's leadership skills, Nico's connection to the underworld and Jason's strategic mind. They join Chaos and are part of a team that has to go on a quest to find some lost artifacts that are crucial in maintaining the balance between order and chaos in the universe. Along the way, they face many challenges, make new friends and enemies, and grow as characters.
Perhaps in the fanfiction, Percy is under some sort of dark influence. This could be from a new, unknown magical force. This influence makes him see Jason as a threat to his friends or himself, so he attacks Jason. Jason, on the other hand, is initially confused but then tries to fight back to defend himself while also trying to figure out what's wrong with Percy.
Well, they could be betrayed by someone they trusted deeply, like a fellow demigod. Maybe this person spreads false rumors about them, leading to their isolation within the demigod community. The three of them would then have to struggle to clear their names and find out who really set them up.
One great fanfiction could be about their adventure in an unknown magical realm. They might have to combine their unique powers - Jason's control over the winds, Nico's ability to summon the dead, and Percy's power over water to defeat a powerful dark force.
One of the common themes in fanfictions involving Percy, Nico, Jason and Chaos could be their epic adventures. For example, they might team up to face a new and powerful threat that emerges from the chaos itself. Maybe they have to journey through different realms, using their unique powers and personalities to overcome obstacles.
The plot could be about them going on a quest to find a powerful, lost artifact. Along the way, they have to overcome their differences. For example, Percy and Nico might have some initial tension due to their different backgrounds, but as they face challenges, they start to understand each other better.
How about 'The Three Heroes'? This name showcases that there are three important members in the band, all of whom can be considered heroes in their own right. They have all had their own heroic adventures in the fanfiction, so it would be a great name to represent them as a band.
One possible reason could be jealousy among other characters. Maybe there are those who envy Percy's powers and leadership, Jason's status as a hero, or Nico's unique abilities. Another reason might be a misunderstanding. For example, they could be wrongly accused of a crime they didn't commit, which leads to others turning against them.