Well, a really cool plot for a Percy Jackson - One Piece crossover fanfiction might involve the search for a powerful and mythical treasure in the One Piece world that has a connection to the Greek gods. The Straw Hat Pirates and Percy's gang could be on a race against some evil force, like a powerful sea devil or a dark sorcerer, who also wants the treasure. Percy could have some knowledge about the treasure's origin from his Greek mythology background, which would be super helpful.
One possible plot could be that the characters from Glitchtale end up in the world of Percy Jackson. Maybe Betty, from Glitchtale, could be mistaken for a new type of monster by the demigods. The demigods then have to figure out whether she's a threat or not. And at the same time, the Glitchtale characters are trying to find a way back to their own world.
Perhaps Percy is on a quest related to Poseidon and accidentally crosses paths with Aquaman. They initially have a misunderstanding, thinking the other is a threat. But then they realize they both have a common goal - to protect the seas. So they team up to stop a group of evil sea witches who are polluting the ocean and causing chaos among the sea life. Aquaman uses his trident and connection to the ocean's life, while Percy uses his sword and his wits to outsmart the witches.
One possible plot could be that the Greek gods, noticing the powerful threats the Avengers face, send Percy Jackson and his friends to help. Percy could use his water powers to assist in putting out fires during a battle like the one in New York. Meanwhile, Thor could be intrigued by Percy's connection to Poseidon and they could exchange stories about their godly fathers.
A great plot could involve a prophecy in both the Naruto and Percy Jackson worlds. The prophecy states that only by combining the powers of the ninja and the demigod can a great evil be defeated. Naruto and Percy are chosen to fulfill this prophecy. Along the way, they face challenges like trying to understand each other's cultures. Naruto has to get used to the Greek pantheon, and Percy has to learn about chakra. They also have to deal with their own insecurities. For Naruto, it could be his fear of not being strong enough without the Nine - Tails' power, and for Percy, it could be his fear of losing his friends in the battle.
One idea could be that Percy and his friends are on a quest and accidentally stumble into Alagaesia, the world of Eragon. There, they meet Eragon and Saphira. The demigods' powers might be seen as strange magic by the people of Alagaesia. Percy could use his water - controlling abilities to help Eragon in a battle against some new threat that is both a danger to the demigods' world and Alagaesia, like a powerful water - based demon. They would have to learn to work together, with Percy teaching Eragon about the modern world's concepts and Eragon showing Percy the ways of magic in his world.
One possible plot could be that the demigods from Percy Jackson's world accidentally stumble upon the Lab Rats' lair. Maybe they are on a quest and get lost in a strange dimension that leads them there. The bionic heroes and the demigods then have to team up to fight a common enemy, like a new type of monster that is part - robotic and part - mythical, created by an evil scientist who wants to take over both the mortal and the demigod worlds.
In a 'naruto garra percy jackson crossover fanfiction', it could start with Percy Jackson being sent to the Naruto universe by some strange magic. There, he meets Naruto and Garra. They soon realize that there are dark forces at work in both their worlds that are connected. They embark on a journey to find the source of this evil. Along the way, Naruto shows Percy his village and the way of the ninja. Garra shares his past and how he overcame his inner demons. Percy, in turn, teaches them about Greek mythology and the powers of the demigods. As they get closer to the source of the evil, they must combine their unique skills and knowledge to defeat it.
One possible plot could be that the Volturi from Twilight discover the existence of demigods from the Percy Jackson world. They see the demigods as a threat to their vampire supremacy. Percy and his friends have to team up with some of the more friendly vampires, like the Cullens, to fend off the Volturi. This would bring together the magic and powers of both universes in an epic battle.
One idea could be that the demigods from Percy Jackson end up in Riverdale due to some sort of magical mishap. Percy could be confused by the strange mortal world of Riverdale, with its own set of secrets and drama. Meanwhile, the Riverdale gang could be in awe of the demigods' powers. For example, Archie might be inspired by Percy's heroism and try to be more like him in facing the town's problems.
Well, it could start with a magical accident. In the Percy Jackson universe, a spell gone wrong sends Percy, Annabeth, and Grover into the land of Alagaësia from Eragon. There, they discover that the demigod powers Percy has are seen as a strange and new form of magic. Eragon is initially suspicious of them but realizes they can help in his fight against Galbatorix. They combine their skills, Percy's water - controlling powers and sword - fighting skills, along with Annabeth's strategic mind and Grover's nature - sensing abilities, with Eragon's dragon - riding and magic - wielding skills to take on the dark forces.