Who could be the main villain in a batman supergirl fanfic?

The main villain could be Darkseid. Imagine if he somehow finds a way to enter the Naruto universe. He would be a formidable foe for both Naruto and Supergirl. His omega beams and immense strength would be a huge challenge for them to overcome.

Another option could be a new villain created specifically for the fanfic. This villain could be someone who has a vendetta against the Wayne family because of something Batman's dad did in the past. He could be a master of disguise and manipulation, making it difficult for Batman and his dad to figure out who he really is.

Ink could be a great main villain. He's a character from the Batman Beyond series known for his ability to manipulate ink - like substances. He could target Robin specifically, seeing him as a weak link in the Batman - Robin duo. His powers would pose a unique challenge for Robin to overcome.

Kingpin would be a very suitable main villain. He has his criminal empire in Hell's Kitchen already, and if he decides to make a move on Gotham, it would bring him into conflict with Batman. His power, wealth, and ruthlessness would make him a formidable foe for the two heroes to face together.

The Joker would be a great choice. He could use some new - fangled chemical or device to mind control Batman. Imagine the chaos he could create with a mind - controlled Dark Knight at his beck and call. He might make Batman do really out - of - character things like laughing hysterically while committing crimes.

Terry McGinnis could face off against a time - traveling Ra's al Ghul. Ra's al Ghul has always been obsessed with immortality and the betterment of the world through his own extreme means. If he had the power of time travel, he could try to reshape history to his liking, which would put him directly at odds with Batman Beyond. Ra's al Ghul's long - term plans and strategic mind would make for a complex and engaging conflict.

The Joker could also be a great choice as the main villain. He's always been obsessed with Batman. Now that Batman is getting married to Wonder Woman, the Joker could feel left out or enraged. He might try to ruin their big day in his own chaotic and unpredictable way. He could also target Wonder Woman as a way to get back at Batman, creating all sorts of mayhem in the process.

Lex Luthor would be a great choice. He could be causing trouble in Gotham as well as Metropolis. His intelligence and resources would pose a significant threat to both Supergirl and Batman. He might be trying to manipulate events to make the two heroes fight each other so he can carry out his evil plans.

Bane could also be the main villain. He's strong enough to physically challenge Batman and has a complex backstory. He could be planning to break Batman both physically and mentally in the game story.

Darth Vader could be a great main villain. His dark power and iconic status in Star Wars would make him a formidable foe for Supergirl. He could see her as a threat to the Empire's rule and try to eliminate her. His mastery of the Force and lightsaber skills would put Supergirl in a tough fight, especially if she's not familiar with the ways of the Force at first.