Another plot could involve the villains from both worlds. Orochimaru from Naruto might be interested in the strange powers and experiments in Deadman Wonderland. He could form an alliance with some of the bad guys there. Meanwhile, the heroes from both universes have to come together to stop this dangerous union. They would have to combine their different fighting styles and strategies to face this threat.
A Harry Potter - Deadman Wonderland fanfiction could focus on the concept of magic vs the extreme and cruel system of Deadman Wonderland. The wizards might be seen as a threat to the order of Deadman Wonderland, and the Deadman Wonderland characters might be in awe or fear of the magic. There could also be a plot where a character has to combine the magical knowledge from Harry Potter with the survival skills needed in Deadman Wonderland to overthrow the corrupt system in Deadman Wonderland.
One idea could be a crossover where Naruto characters are trapped in Deadman Wonderland. For example, Naruto could use his shadow clones to deal with the various challenges and enemies in the prison. Another idea is to explore how the powers in Deadman Wonderland would be used by Naruto characters. Maybe Sasuke could master some of the blood powers in a unique way. And a third idea could be a story where the main Naruto characters have to form alliances with the Deadman Wonderland inmates to escape the prison together.
One interesting plot could be Naruto mastering a new and extremely powerful genjutsu that even the strongest shinobi can't break. He might use it to defeat a great enemy that was thought to be invincible. Another could be Naruto using his genjutsu god - like powers to enter the minds of his friends and heal their inner traumas.
In Naruto reincarnation of Kaguya fanfiction, there could be a plot where Naruto discovers that he has the ability to open new dimensions like Kaguya did. This would give him an edge in battles but also attract unwanted attention from other powerful forces. Also, the story could revolve around Naruto trying to understand Kaguya's true motives for creating the chakra system. By doing so, he might find a way to make the shinobi world a better place, perhaps by redistributing chakra more fairly or something similar.
A great plot might involve a character who has the Fourth Dojutsu but has to keep it a secret from everyone. As they struggle with this burden, they start to realize that there are dark forces that are aware of their power and are trying to manipulate them. This creates a lot of internal and external conflict for the character.
Perhaps a plot where Naruto is influenced by an evil godlike entity. This entity could be from a different dimension. It whispers dark thoughts into Naruto's mind, gradually turning him against the values he once held dear. As a result, he starts to perform actions that are completely out of character for the original Naruto, like attacking innocent villages to gain more power.
There's also a plot where Madara and Naruto are the only two people left in a post - apocalyptic shinobi world. They must rely on each other to survive and in the process, they discover new aspects of themselves and their powers. This plot is full of action and also explores their emotional connection in a desolate setting.
Some fanfictions might focus on the psychological effects of the mind control jutsu. For example, if a character is under mind control for a long time and then is freed, how do they deal with the memories of what they did while controlled? It could be a very emotional and character - driven story. Maybe they struggle with guilt or fear of being controlled again.
One interesting plot could be that Naruto awakens the Sharingan during a battle with a powerful new enemy. This unexpected turn gives him new abilities like predicting the enemy's moves better. Another plot might involve Naruto getting the Sharingan in a dream and then slowly learning to use it in the real world. It could also be that Naruto inherits the Sharingan from a long - lost relative, which changes the whole dynamic of his relationships in the ninja world.
A plot that stands out is when Hashirama, through Edo Tensei, has to team up with modern - day ninjas against an ancient evil that has been resurrected. It's interesting because it combines the old - school power of Hashirama with the new techniques of the current ninja generation.