Maybe the protagonists will be a group of rebels. After the events of the previous books, there could be a new wave of resistance. These rebels might come from different backgrounds and have different motives, but they all aim to overthrow the Capitol. Their stories could be intertwined as they work together towards this common goal in the new Hunger Games novel.
It could be a new tribute from an overlooked district. Maybe someone who has a special skill or a unique background that sets them apart.
It's possible that there will be a character who has a connection to the later main characters in the original Hunger Games story. Maybe a relative or someone who inspired them in some way. This character could be the center of the prequel's plot, and through their story, we can see how the events of the prequel lead to the situation in the original Hunger Games.
There could be a character from one of the districts who was among the first to oppose the Hunger Games. This person might be a leader figure in the early resistance. It could also be a mentor - like figure who trained the first tributes. They would be important as they could show the different reactions of people to the emerging Hunger Games system.
The children of the original protagonists could be new protagonists. For example, Katniss and Peeta's child might grow up in a world that is still full of challenges. They would have to deal with the legacy of their parents while also forging their own path in the new Panem.
There could be the predecessors of the Gamemakers. They would be important as they are the ones who design the Hunger Games.
Katniss and Peeta would probably still be main characters. Their relationship from the original Hunger Games could be further explored in the context of this new marriage - based game. They might have to deal with new challenges to their relationship, like how to balance their individual goals with the expectations of this new game format.
Since it's not out yet, we can't be sure. But it could be descendants of the original characters like Katniss and Peeta. Or it might introduce entirely new characters from districts we haven't seen much of before.
Finnick and Annie could also be featured. Their love story in the Hunger Games was very touching. A wedding fanfiction about them could explore their post - Games life and how they build their new life together. Also, Effie could be in it. She has a unique personality, and her presence at a wedding could bring some Capitol - style glamour and also some comical moments as she tries to understand the more down - to - earth district wedding traditions.
The Shredder would be a likely villain. He could see the Hunger Games as an opportunity to finally get rid of the TMNT. He might manipulate the other tributes or even work with the Capitol to set up traps for the Turtles.
Elsa would be a strong contender. Her ice powers give her a huge advantage. She can defend herself easily and attack from a distance. Also, she has shown great self - control in difficult situations in her own story. But Anna also has a chance. Her determination and ability to make friends quickly could help her form strong alliances and survive.