The combination of different power systems. Naruto has his chakra and various jutsu, while Kingdom Hearts has magic and keyblades. Seeing how these interact, like Naruto using his Rasengan with the help of Kingdom Hearts' magic, is really exciting.
The new settings that are created. When Naruto enters the Kingdom Hearts worlds or vice versa, we get to see familiar places from both franchises in a new light. For instance, if Naruto ends up in Traverse Town, how would he adapt to this strange new place filled with different species and the ever - present threat of Heartless? It adds a whole new layer of adventure and exploration to the story.
One key element is how Naruto's godlike powers are translated into the Kingdom Hearts setting. For example, his Rasengan could be reimagined as a powerful attack against the Heartless.
Character interaction is a key element. Axel interacting with characters from different universes can lead to interesting dynamics. For example, his fiery personality might clash or blend well with more reserved characters.
The combination of different abilities. Naruto characters have ninjutsu and chakra powers, while Metal Gear has advanced technology and stealth skills. When these are combined, like Naruto using his Rasengan while sneaking around Metal Gear's high - tech bases, it's really exciting.
Well, a really exciting plot might involve characters from different worlds within the Kingdom Hearts universe who were previously thought to be lost or dead suddenly reappearing during the Keyblade War. They could bring with them new powers or knowledge that shakes up the whole conflict. For example, if a character from a long - forgotten world shows up with the ability to nullify certain Keyblade attacks, it would completely change the dynamics of the battles. There could be a race among the warring factions to either recruit this character or eliminate them. And as the story unfolds, we could see how the different Keyblade wielders' loyalties are tested in the face of this new threat or opportunity.
One popular theme is the clash of different power systems. For example, how Sonic's super forms compare to the power of the Keyblade. Another is the exploration of different worlds. Authors like to put Sonic characters into the unique and often beautiful or dangerous worlds of Kingdom Hearts.
One interesting storyline could be Sora and the gang from Kingdom Hearts getting lost in the world of DuckTales. They could team up with Scrooge McDuck to search for a special keyblade that's hidden in one of Scrooge's many treasures. This would bring together the magic of Kingdom Hearts and the adventure - seeking nature of DuckTales.
Another interesting pairing could be Sakura and Kairi. Sakura is a strong - willed kunoichi who has grown from being a bit of a fangirl to a capable fighter. Kairi is also a strong - hearted girl. They could bond over their experiences of being in the background sometimes but still being important to their respective groups. They might even learn some new self - defense moves from each other.
One possible plot could be that Naruto and his friends are somehow transported into the Kingdom Hearts universe. Naruto, with his never - give - up attitude, could team up with Sora to fight against the Heartless. They might learn new techniques from each other. Naruto could teach Sora some of his ninja skills like shadow clone jutsu, and Sora could show Naruto how to use the Keyblade more effectively in combat.
One idea could be exploring a new world based on a classic fairy tale not yet included in the series. For example, a world of the Brothers Grimm's 'The Snow Queen'. Sora could face new challenges there, like dealing with the cold magic of the Snow Queen herself. Another could be delving deeper into the backstory of some of the lesser - known Organization XIII members in the context of Kingdom Hearts 4. Maybe there's a hidden past that ties them to a new threat in this fanfiction.
The most interesting part is the crossover of characters. Seeing Sora interact with Luke Skywalker, for example, is really cool. They come from different universes with different powers and moral codes, but in the fanfiction, they can learn from each other.