Maybe the Wood Dragon Slayer has a connection to the Sage of Six Paths. This connection gives them unique abilities that no one else has. They could discover this connection during a dangerous mission in an ancient ruin. And then they have to learn how to control these newfound powers while also dealing with the political unrest in the village that arises from others fearing their new strength.
Well, one idea could be the fusion of Naruto's ninja skills with crystal dragon slaying magic. Maybe Naruto discovers a hidden power within him that allows him to summon crystal dragons and use their powers in battles against powerful foes in the Naruto universe.
One idea could be that Naruto discovers he has the power to slay golden dragons during a mysterious mission in a hidden land. Maybe the dragons are guarding an ancient power that could change the ninja world.
One plot idea could be Naruto being transported to the world of Dragon Slayers and having to learn their magic to get back home. He might combine his ninja skills with the new magic he acquires. Another could be a team - up between Naruto and Natsu to fight a common enemy that threatens both their worlds. Maybe a dark force is trying to merge the Naruto universe and the Dragon Slayer universe and they have to stop it.
One idea could be a crossover where a Fire Dragon Slayer from Fairy Tail ends up in the Naruto world. They could use their dragon slayer magic to fight alongside the ninja against a common enemy, like a powerful new Akatsuki member with fire - based abilities. The Fire Dragon Slayer's unique skills, such as eating fire to regain strength, would be a fascinating addition to the Naruto battles.
One idea could be a crossover where Naruto meets a shadow dragon slayer from another dimension. They could team up to fight a common enemy that threatens both their worlds. Maybe a powerful dark wizard who wants to steal Naruto's chakra and the dragon slayer's magic.
Maybe Gray has to team up with a dragon in order to defeat an ancient evil that threatens to destroy the world. The dragon could have its own motives and Gray has to figure out if he can trust it.
The titanium dragon slayer could be cursed. Every time they attempt to slay a dragon, they are instead inflicted with a part of the dragon's power, slowly turning them into a half - dragon, half - slayer hybrid. This transformation makes them an outcast among their own kind and forces them to reevaluate their role in the world of dragon slaying.
One idea could be that the poison dragon slayer has to overcome a rare and powerful poison - based curse that is slowly sapping their strength. They must find a mythical antidote hidden in an ancient dragon's lair.
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.
One idea could be Juvia discovers a new water - based magic that only water dragon slayers can use. It gives her the ability to transform water into different forms, like crystal - like structures for defense. Another could be a time - travel plot where Juvia goes back in time and meets the first water dragon slayer and learns ancient techniques from them. And a third idea is that Juvia has to team up with other dragon slayers to defeat a powerful water - based villain who is misusing water magic and causing chaos.