The main character has to be Danny Phantom. He has his own set of powers that he'll use to prank. In the Justice League, Superman will be a major character. His invulnerability and super - strength might not be much help against Danny's ghostly tricks. Wonder Woman with her strength and combat skills could also be a target. And Green Lantern, with his power ring, would be interesting to see how he reacts when Danny messes with his ring or the constructs he creates. Aquaman too, as his connection to water could be a target for Danny's pranks.
Obviously, Danny Phantom is one of the main characters as the title implies he's the one doing the pranking. And then, members of the Justice League like Superman, Batman, Wonder Woman, Flash, etc. would be the ones being pranked.
Danny Phantom is for sure the main character on the saving side. On the Justice League side, all the classic members would probably be there. Superman, being the symbol of hope and having super strength, heat vision etc. Batman, the Dark Knight with his gadgets and detective skills. Wonder Woman with her Lasso of Truth and superhuman strength. The Flash, who can move at incredible speeds. Green Lantern, who can create constructs with his power ring. And Martian Manhunter, with his shape - shifting and telepathic abilities. They all could be in danger and Danny would have to figure out how to save each of them based on their unique powers and vulnerabilities.
Well, Danny could use his ghostly powers to play all sorts of tricks on the Justice League members. Maybe he turns Superman invisible for a while just to see his confusion. Or he makes Batman's utility belt float away when he's in the middle of a fight.
I think Superman would be the most likely. Superman is known for his kind heart and open - mindedness. He would probably see Danny as a young hero in need of some guidance and friendship. He wouldn't be too quick to judge Danny based on his ghostly appearance or powers.
I think there's no clear - cut winner in a 'danny phantom vs justice league' fanfiction. Danny Phantom is a powerful ghost - hero in his own right. He has unique powers that the Justice League may not be familiar with at first. But the Justice League is a team of some of the most powerful heroes in the DC universe. If the story is written in a way that Danny has some sort of ace up his sleeve, like a new power or a powerful ghost artifact, he could potentially defeat the Justice League. On the other hand, if the Justice League is well - prepared and uses their combined skills effectively, they could overpower Danny.
I think it could be Superman. Superman is all about truth and justice and he would likely see the good in Danny. Also, they both have super strength in a way. Danny has his ghostly strength and Superman has his Kryptonian strength. They could bond over protecting the innocent.
Obviously, the main character would be Danny Phantom himself, but in two different forms or versions. One would be the original Danny Phantom from the canon source, and the other would be a version created by the fanfiction. There might also be his friends like Sam and Tucker who could play important roles in helping the two Dannys understand each other and deal with any issues that arise from their meeting.
Danny Phantom himself is obviously very popular as he is the main character from his own series. His ghost - fighting abilities and his dual identity make him an interesting addition to the Justice League universe.
Obviously, Danny Phantom and Ember would be the main characters. Danny is the half - ghost protagonist who is being raised by Ember. Ember, a ghost with music - related powers, would play the role of his caretaker or mentor in this fanfiction.
The characters interact in various ways. Danny could be called upon by the Justice League to deal with a particular threat that has a connection to the Ghost Zone. He would then have to work alongside heroes like Superman or Batman. Superman might be curious about Danny's powers, as they are so different from his own. Batman, of course, would be analyzing Danny's abilities and trying to find any potential weaknesses. Danny's enemies from his own series could also be involved, and the Justice League would have to learn how to deal with these new types of foes.
Danny could use his ghostly powers to disrupt the technology that some Justice League members rely on. For example, he could mess with Cyborg's systems. His ability to overshadow people might also be a key factor, allowing him to control some of the less - powerful members.