A really cool aspect in some crossovers is how the different power - ups work. For instance, if a character from Fairy Tail were to get a Keyblade, they would have to learn how to use it in addition to their own magic. This could lead to some really creative storylines, like Lucy using her Celestial Spirit Magic along with a Keyblade to defeat enemies in a way that neither series has seen before.
One interesting concept could be the combination of different magic systems. In Fairy Tail, there are various types of magic like fire, ice, and celestial magic. In Kingdom Hearts, there's magic related to the Keyblades. In fanfiction, authors might create new spells by merging these two magic systems. For example, a Keyblade wielder using Fairy Tail - style fire magic to enhance their attacks.
One interesting fanfiction could be about Sora and the Fairy Tail gang teaming up to fight a new, powerful dark force. It might have epic battles and cool magic combinations.
Some crossovers might involve the villains. Orochimaru could be interested in the power of the Heartless or the Keyblades. He might try to manipulate the situation in the Kingdom Hearts world. And the Organization XIII members could see Naruto's unique powers as a threat or a tool for their own plans. This would lead to some intense battles and strategic alliances between the characters of both series.
A great aspect of a Final Fantasy 10 and Kingdom Hearts fanfiction crossover could be the character relationships. Yuna and Sora, for instance, could form an interesting friendship. Yuna's calm and spiritual nature might contrast and complement Sora's more impulsive and adventurous side. They could learn from each other's experiences, with Yuna teaching Sora about the summoning and the fayth, while Sora shows Yuna the power of the Keyblade and the importance of believing in oneself in the face of great evil.
Sora would probably be a very powerful addition to Fairy Tail. His skills with the Keyblade could be used in interesting ways against the various dark forces in the Fairy Tail world. He might form strong friendships with the guild members, like he did in his own world, and share his stories of different worlds he has visited.
A really cool concept could be the Warhammer magic items being introduced to the Fairy Tail world. Imagine if Gray got his hands on a Warhammer frost weapon. It could enhance his ice - make magic in ways he never thought possible. And the different magical lore from Warhammer could inspire new spells among the Fairy Tail mages.
One idea could be that the characters from Kingdom Hearts have to team up with Fairy Tail wizards to defeat a new powerful dark force that threatens both their worlds. This dark force could be stealing the keyblades' power and the magic of Fairy Tail. Another plot could involve a character from Kingdom Hearts getting lost in the Fairy Tail world and having to learn magic to find their way back home while also helping Fairy Tail with their own problems, like fighting a guild that has turned evil. And a third plot could be about a Fairy Tail wizard finding a keyblade and having to learn how to use it with the help of Sora and his friends to stop an ancient evil that is starting to awaken in both worlds.
One interesting crossover could be the characters' power - ups. For example, Sora from Kingdom Hearts might learn some ki - based attacks from the Dragon Ball Super characters. This would be a cool blend of the two universes' fighting styles.
The Kingdom Hearts and Harry Potter crossover is quite popular. You can have Sora and his friends exploring Hogwarts. The contrast between magic in the two universes is fascinating. For instance, Keyblade wielding in the halls of Hogwarts is an amazing concept.
One great Kingdom Hearts crossover in fanfiction is with Final Fantasy. The different worlds and characters blend really well. For example, Sora meeting Cloud in a unique setting. It adds a new layer of adventure and character development.