Who would be the main antagonist in a 'Batman meets Justice League' fanfiction?

It could be the Joker. Since he's one of Batgirl's main foes in Gotham, his chaotic nature would pose a great threat to the Justice League as well when they enter Gotham's affairs.

Obviously, Batman and the members of the Justice League are the main characters. Batman is the Dark Knight, known for his intelligence and combat skills. And then there's Superman, the Man of Steel with super strength and other powers. There's also Wonder Woman, a powerful Amazon warrior.

The Joker could be a great antagonist. Imagine him being intrigued by the formation of the Justice League after Batman's start in 'Batman Begins'. He could see it as a new toy to play with and start causing chaos in a way that targets both Batman's Gotham roots and the League as a whole. He might use his mind games to try and turn the League members against each other.

The Riddler could be a great antagonist. He might have a grand scheme that not only affects Gotham but also has implications for the Justice League's interests. His riddles could stump both Robin and the League members, forcing them to work together to decipher his plans.

It could be a new villain who has a vendetta against both Batman's family (including Batmom) and the Justice League. Maybe a powerful criminal mastermind who has studied both sides and found their weaknesses.

In addition to Batman, Superman, and Wonder Woman, The Flash could also be a main character. His super - speed would add an element of quick - paced action and his humorous personality would provide some levity. Aquaman, with his connection to the ocean and his trident, is also likely to be a main character. He can bring in a different perspective, especially when it comes to underwater or environmental threats. Green Lantern, with his power ring and willpower, would also be important as he has unique abilities that can be used in various ways to fight threats.

Ink could be a great main antagonist. He has the power to manipulate shadows and could use this ability to create chaos in Gotham and beyond. He might target the Justice League and Batman Beyond because they represent order and he wants to spread his own brand of darkness.

Batman Beyond would be the most interesting. He's a new take on the Batman concept with his high - tech suit and different personality compared to the original Batman. He has to prove himself to the Justice League and show that he's just as capable, if not more so, in his own time.

The Riddler could be a great main antagonist. He loves to create complex puzzles and mysteries, which would be right up Sherlock Holmes' alley. And of course, Batman has had his run - ins with the Riddler in Gotham. Holmes' deductive skills and Batman's combat and detective skills would be put to the test trying to outwit the Riddler's convoluted plans.

The main antagonist would be the Flashpoint Joker. In the Flashpoint universe, he is likely to be even more dangerous and unhinged. He could be targeting Batman directly or causing destruction that Batman feels responsible for stopping. His presence would drive the plot forward as Batman tries to outwit and stop him.