One idea could be that the main character, who has the power of a Sky God Slayer, teams up with Naruto to fight a new, powerful enemy that threatens the ninja world. This enemy could be manipulating the weather in a destructive way.
A cool plot could involve the Sky God Slayer's power being linked to an ancient prophecy in the Naruto universe. The main character discovers that they are the key to preventing a cataclysmic event. Along with Naruto and his friends, they embark on a journey to find the source of the threat and use their unique powers to stop it.
A plot could involve a Fire God Slayer from another dimension accidentally ending up in the Naruto world. This character then has to find a way back home while also getting involved in the local politics and power struggles. They might use their Fire God Slayer powers to help the oppressed in the ninja villages, creating both allies and enemies along the way.
One idea could be a story where the protagonist, inspired by the Lightning God Slayer concept, develops a new jutsu that can counter the most powerful lightning - based attacks in the Naruto universe. This new jutsu could be a combination of wind and water elements to short - circuit the lightning.
Maybe in the fanfic, Percy teams up with some unexpected allies, like a group of minor gods who also feel threatened by the more powerful gods' actions. Together, they form a plan to slay a corrupt major god, which involves traveling to different realms and facing various mythical creatures along the way. The story could explore themes of friendship and betrayal as they work towards their goal.
One idea could be a story where the main character has the ability to slay phoenixes and is a new, powerful ninja in the Naruto world. They could be on a quest to find a rare phoenix that has the power to grant a wish.
A great plot idea could be that a powerful dark force is emerging that is draining the energy of all three worlds. The Naruto characters, Fairy Tail wizards, and Dragon Slayers must team up. They start by having a big meeting to share their knowledge and figure out a plan. Along the way, they have to overcome their differences in fighting styles and beliefs.
You could start by creating a character who is from a far - off land where the Sky God Slayer powers are known. This character arrives in the Naruto world and has to adapt to its different rules and cultures while still using their powers. For example, they might have to learn how to use their powers without disrupting the chakra system that is so fundamental in Naruto.
One interesting plot idea could be the exploration of how Naruto's powers interact with primordial god - like abilities. For example, if he gains the power to control the elements in a more fundamental way than just the regular chakra - based elemental control.
One interesting plot idea could be the discovery of a new and extremely powerful bloodline within the Naruto universe in the 'naruto slayer bloodline fanfiction'. Maybe a character who was thought to be weak suddenly unlocks this bloodline and has to deal with the newfound power and the attention it brings.
Well, a really interesting plot idea might be that the Ice God Slayer comes from a different dimension where ice is the main source of power. In the Naruto world, they have to adapt to chakra. So, the story could be about how they balance their ice god slaying powers with chakra. Maybe there's a villain who wants to steal the Ice God Slayer's power to control both ice and chakra, and Naruto has to help stop this. Also, the Ice God Slayer could have a special bond with an ice - based creature in the Naruto world, like a rare ice fox, and they go on adventures together with Naruto.
One interesting concept could be the combination of Naruto's world with god - slayer magic. It might introduce new power dynamics and character developments. For example, Naruto characters could gain the ability to slay gods, which would completely change the power scale in the Naruto universe.