One idea could be exploring how Batman's allies step up in his absence while he's recovering from a broken back. For example, Robin might take on more responsibilities in protecting Gotham.
It might also show the villains' reactions. Some villains might see it as an opportunity to take over Gotham, while others might be hesitant because they respect Batman so much that attacking when he's down seems unfair.
The other members of the Bat - family like Robin, Nightwing, and Batgirl are likely to be main characters too. They would be involved in filling the void left by Batman in protecting Gotham.
One interesting plot could be a story where Batman's son has to take over Gotham while Batman is away on a long - term mission. He faces challenges from old villains who think he's an easy target.
Another idea might be that one Batman is from the future and has come back to meet his past self. The future Batman could show the past version some new technologies and tactics, but also warn him about the potential consequences of certain actions. This could lead to self - reflection for the past Batman and a change in his approach to crime - fighting.
One idea could be a story where Robin has to take on Batman's role temporarily when Batman is injured. He has to face a powerful villain all on his own, using the skills Batman taught him in a new and creative way.
One idea could be a crossover where Naruto is transported to Gotham City. He might use his ninja skills to help Batman fight the villains in a new and unexpected way. For example, his ability to move quickly and stealthily could be a great asset in tracking down the Joker.
One idea could be a story where Batman and Hawkgirl team up to stop a powerful villain that is causing chaos in both Gotham and Hawkgirl's home realm. They start off not trusting each other fully due to their different methods, but as they face challenges together, they learn to respect and rely on one another.
Another idea could be the contrast between Batman's brooding and often solitary nature and the more community - based and female - dominated society of Themyscira. This could lead to some character development for Batman as he learns new ways of interacting and trusting others.
One idea could be a crossover where Batman and the Turtles team up to take on a common enemy like the Foot Clan and some of Batman's rogues gallery working together. Maybe they meet in Gotham City and have to adapt to each other's fighting styles.
One idea could be a story where Batman and Wolverine team up to take on a powerful new villain in Gotham City. The contrast between Batman's high - tech gadgets and Wolverine's brute strength would make for an exciting dynamic.
In some Punisher Batman fanfiction, the setting might be a Gotham overrun by more extreme and violent criminals. The Punisher could come to Gotham thinking he can clean it up better than Batman. This would lead to a power struggle and also a chance for them to learn from each other's techniques.