In a more extreme scenario, Deadpool could end up in Arkham Asylum and think it's a new kind of S.H.I.E.L.D. facility. He'd start interacting with the inmates there, and Batman would have to step in to deal with the chaos Deadpool is causing. Deadpool would see Batman as this dark and brooding figure and keep trying to get him to lighten up.
The key characters are Batman, Superman, and Lex Luthor. Batman is the Dark Knight, a vigilante with no superpowers but great detective skills and combat abilities. Superman is the Man of Steel, an alien from Krypton with super strength, speed, and other amazing powers. Lex Luthor is a brilliant but devious billionaire who sees Superman as a threat to his own power and plans to destroy him by pitting him against Batman.
Lois Lane is often a popular character. In fanfiction, she might play a crucial role in mediating between Batman and Superman or getting involved in their adventures in a more hands - on way, using her investigative journalism skills.
In a 'deadpool meets batman fanfiction', there could be a lot of chaos. Deadpool's wild and unpredictable nature would clash with Batman's brooding and serious demeanor. Maybe Deadpool would constantly crack jokes and annoy Batman. He might also try to get Batman to lighten up and break some of his strict rules.
One main plot point is the ideological clash between Batman and Superman. Batman sees Superman as a potential threat to humanity due to his god - like powers. Superman, on the other hand, is just trying to do good but is often misunderstood. Another point is Lex Luthor's manipulation. He fuels Batman's distrust of Superman and sets them on a collision course. Also, the discovery of Kryptonite by Batman gives him a means to potentially defeat Superman in a fight.
One interesting plot could be Batman and Superman having to team up against a common enemy that is more powerful than either of them alone. This forces them to put aside their differences and combine their skills.
One possible plot could be that Deadpool is hired by a mysterious villain to steal something from Batman. But when Deadpool realizes it's Batman he's up against, he decides to have some fun with it instead of just doing the job. He starts leaving crazy clues and taunting Batman in his own wacky way. Batman, of course, is initially frustrated but then starts to figure out Deadpool's pattern and tries to use it against him. In the end, they might end up having to team up to stop the real bad guy who hired Deadpool in the first place.
It depends on the situation. If it's in Gotham, Batman has the home - field advantage. He knows the city like the back of his hand and has all his gadgets and traps set up. But Deadpool is really hard to kill. He could keep coming back at Batman no matter how many times he's knocked down. So it could be a never - ending fight with no real winner.
Maybe in the fanfiction, Batman is on a mission in another city and runs into Deadpool. Deadpool mistakes Batman for some kind of anti - hero like himself. He tries to befriend Batman and convinces him to break some of his no - killing rules just for one mission against a really bad guy. This could lead to a lot of moral and ethical debates between the two characters as they work together.