Maybe there's a place in the fanfiction world that has been dried up, like an old, forgotten lake that was once a powerful place for the gods. Percy finds it and decides to 'just add water' to it. As he does, it resurrects an entire civilization of water - based creatures that were thought to be extinct. These creatures have their own culture and rules, and Percy has to navigate between their world and the world of the demigods, trying to keep the peace and also find a way to use their ancient knowledge to stop a new threat to Camp Half - Blood.
Water can be unique as it could have different properties in the fanfiction. For example, it might be able to heal any wound if it's from a certain magical source. Percy could discover this water and use it to save his friends. It would be a game - changer in battles and conflicts.
Well, it could be about Percy discovering new powers over water. Maybe he can control not just regular water but also things like water in plants or even in the clouds. He could use these new powers to defeat some really powerful ancient monsters that are immune to normal demigod attacks.
Maybe in the fanfiction, the zoo is a place where the gods have hidden some of their lost magical artifacts. Percy, being the son of Poseidon, senses a strange water - based magic near the aquarium section. He starts to investigate with Annabeth. Along the way, they face challenges from zoo security (who are unknowingly being influenced by a minor god who doesn't want the artifacts found) and various magical traps set around the exhibits.
A plot could involve Percy being sent to Forks on a quest. He discovers that there's a powerful artifact hidden in the area that could cause chaos if it falls into the wrong hands. The vampires and werewolves in Forks are also after this artifact for their own reasons. Percy has to navigate the complex relationships between these two groups while also trying to keep his true identity as a demigod a secret. Along the way, he forms an unlikely friendship with Jacob, who helps him understand the ways of the werewolves.
One possible plot could be Percy arriving in the DxD world and being mistaken for a new, extremely powerful devil. He then has to navigate the complex politics of the devils while also trying to find a way back home. Along the way, he uses his demigod powers in unique ways against the various threats in the DxD universe.
A plot could involve a new character who is jealous of the mermaids' abilities in 'H2O: Just Add Water'. This character kidnaps one of them to try and take their powers for themselves. The kidnapped mermaid has to figure out how to escape while her friends search for her. They could face many obstacles like false leads and traps set by the kidnapper. In the end, they would likely use their friendship and unique skills to overcome the situation.
Another interesting plot might involve Percy facing off against other gods. As the God of Water, he could be seen as a threat or a potential ally. Some gods might try to undermine him, while others might seek his help. This could lead to political intrigue within the pantheon, which is always exciting in fanfiction.
A plot idea could be that Bella accidentally loses her powers and Will has to help her get them back. He takes her to a special place underwater that is said to have the ability to restore lost powers. During this time, they have to overcome many obstacles like strong currents and unfriendly sea creatures. This experience makes their bond even stronger.
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.
Well, perhaps there's a villain in the Percy Jackson universe who discovers that the iCarly web show has a huge following and decides to use it as a way to spread chaos. The demigods have to team up with the iCarly crew to stop this. The iCarly gang has to learn about the world of Greek mythology really fast and help the demigods navigate the modern world of technology and media to defeat the villain.