If Batman got superpowers, perhaps he could have the power of flight. This would give him a huge advantage in Gotham. He could quickly reach any crime scene in the city, and also chase down villains who try to escape using airborne vehicles. It would also make his presence more intimidating as he could swoop down on criminals from above.
He might become more confident, bordering on overconfident at times. With superpowers, he would have a greater sense of invincibility, which could make him a bit more reckless in his actions compared to his non - superpowered self.
Well, it could be that in the fanfic, Batman encounters an ancient artifact. This artifact, when he touches it or unlocks its secrets, endows him with superpowers. It might be something that was created by an alien race or an ancient civilization with advanced technology that they left behind on Earth, and Batman, being the detective he is, stumbles upon it and gets these amazing powers.
He might become more confident. Normally, Batman has to rely on his wits and training. But with superpowers, he'd have an extra edge. For example, if he had the power of invisibility, he could infiltrate enemy lairs more easily. This newfound ability could make him a bit cocky at first, thinking he doesn't need his usual caution. But he'd soon realize that his superpowers are just another tool in his fight against crime, and he'd need to balance them with his existing skills.
It would add a new layer of complexity to the Batman mythos. Batman is often portrayed as a lone, brooding figure, but a cheating incident in his love life would make him more relatable. It could also change how other characters view him, perhaps with some pity or a new understanding of his flaws.
The dog could make Batman more empathetic. He's so used to dealing with the dark side of Gotham that having a dog would bring out his softer side. He might become more protective not just of Gotham but also of this small, vulnerable creature in his care.
One idea could be that Batman gains the power of super strength. He could use this to take on villains like Bane more easily, lifting heavy objects to block attacks or overpowering his foes in hand - to - hand combat. Maybe he gets this power from an experimental serum he was testing in the Batcave.
One possible plot could be that Batman discovers his love interest, perhaps Catwoman or someone else, has been unfaithful. This could lead to a downward spiral for Batman, making him question his judgment not only in love but also in his crime - fighting. He might become more withdrawn and angry, causing issues in his relationships with Alfred and the Justice League.
In some fanfictions, Batman's superpowers could come from a genetic mutation. Maybe there was a hidden aspect of his family's genetics that was activated by some external factor, like a new type of chemical in the air in Gotham. This would be a scientific approach to giving him powers.