Well, Batman himself is likely to be one of the main characters. He would be the one trying to deal with the situation involving the splicers. There might also be some new characters created specifically for this fanfic that are related to the splicers, perhaps a leader among them or a scientist who created them.
There could be some new characters who are splicers themselves. Maybe a lead splicer character who is trying to create a new world order for the splicers. This character could be complex, having both good intentions for his splicer kind but going about it in the wrong way, like causing chaos in Gotham.
The way the fanfic might re - imagine the setting of Batman Beyond is also appealing. It could update the technology or the social environment of the city. The splicers could be a product of some new scientific experiment gone wrong in this updated world. This could lead to a lot of exciting action scenes as Batman tries to keep the city safe from the chaos they cause.
Bruce Wayne is also important. Even though he's older, he still plays a significant role. He mentors Terry and provides him with the knowledge and resources to be Batman. Their relationship is a key aspect of the story. Additionally, characters like Max could also be main characters. She's Terry's friend and often gets involved in his adventures, sometimes helping him out with her hacking skills and general intelligence.
In the 'Batman Beyond Splicers Fanfiction', we might see new gadgets being introduced to deal with the splicers. Since the splicers have different biological make - ups, Batman might need to develop specialized weapons or tools. For instance, a device that can disrupt the spliced DNA temporarily to weaken the splicers during a fight.
Definitely Terry McGinnis. He's the central figure in Batman Beyond and in fanfic, his story can be told in so many different ways. He has to balance his normal life as a teenager with his superhero duties. Then there's Inque. She's a really cool and unique villain in the Batman Beyond universe. In fanfic, she can be made even more menacing or given a more complex backstory. And let's not forget Brother Eye. It's a super - interesting concept that can be explored in great detail in fanfic, adding new layers to the Batman Beyond world.
Terry McGinnis is bound to be a main character. He is Batman in this future setting. His alter - ego as a young man trying to balance his normal life and his duties as Batman would be central to the story.
Terry McGinnis as Batman is one of the main characters for sure. There's also likely to be Bruce Wayne, who mentors Terry.
Another character could be Terry's love interest. She could play a role in the twins' story, perhaps she has a connection to their past or she gets caught in the middle of their conflict with Batman Beyond, making the story more complex and engaging.
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.
Robin, in all his incarnations, is also a popular character in fanfiction related to Batman. He represents the sidekick aspect and the growth and development that comes with it. In Batman Beyond, Commissioner Barbara Gordon also features prominently in some fanfictions. Her connection to the original Batman era and her role in the new one can be explored in interesting ways.