The main characters are obviously Jack Frost and the Guardians. The Guardians typically include characters like North (Santa Claus), Tooth (the Tooth Fairy), Bunny (the Easter Bunny), and Sandy (the Sandman).
In this fanfiction, Elsa and Jack Frost are the main characters. Elsa is a complex character, initially feared in her own kingdom because of her powers. Jack Frost, on the other hand, is a more free - spirited character who loves to play with children and spread winter magic. Their meeting in the fanfiction likely brings out new aspects of their personalities as they interact.
There could be the Guardians. They might play a role in the story. For instance, they could be initially hesitant about Jack Frost's sister being around, fearing she might disrupt the balance. But as they get to know her, they become friends. North could be there, with his jolly self, giving the sister a little magical gift.
One idea could be that Jack Frost discovers a new hidden power within himself while interacting with the Guardians. This power could be related to an ancient magic that the Guardians didn't know about. Another plot could involve Jack Frost having to prove himself to a skeptical Guardian who doesn't believe he's worthy of being part of the group. And a third plot idea might be that Jack Frost and the Guardians team up to face a new and powerful enemy that threatens the balance of the world they protect.
Pitch Black would be a likely main antagonist. He could manipulate Jack Frost into turning dark, as he has a history of preying on the insecurities of the Guardians.
Thor might be a great ally for Jack Frost. Thor is used to dealing with magic and powerful beings from different realms. He would be less likely to be intimidated by Jack Frost's powers. They could both use their elemental - related powers (Thor with lightning and Jack Frost with ice) to create powerful combined attacks against their enemies. For example, Thor could strike his lightning into Jack Frost's ice structures, creating a powerful blast of energy.
His parents could be in his family. Maybe his father is an ancient frost giant with great power over ice and snow, and his mother could be a gentle spirit who gives life to the frozen landscapes. There might also be siblings, like a sister who can create beautiful ice flowers.
A powerful ice - demon could be a great antagonist. It could be jealous of Jack Frost's power over winter and Danny's ghost powers, so it tries to take over their powers and rule both their worlds.
Well, in this kind of fanfiction, the relationship between Jack Frost and the original character (OC) can be really diverse. It could be a friendship where they start off as strangers and gradually become close pals, perhaps sharing their unique powers and experiences. For example, the OC might have a special power related to nature, and they team up with Jack Frost to protect the world from some dark force.
Obviously, Jack Frost is the main character as the story is about his transformation into a dark version of himself. But there could also be other characters from the original Jack Frost lore, such as the Guardians like North, Bunny, and Tooth. They would likely play important roles, either trying to save Jack from his dark path or being forced to oppose him if he becomes too dangerous.
The main characters are obviously Jack Frost and Baby Tooth. Jack Frost is often depicted as a fun - loving, mischievous spirit of winter. He has the power to control ice and snow. Baby Tooth, on the other hand, is a tooth fairy. She is very small and cute and has a big role in collecting teeth from children. In fanfiction, they usually interact in various ways, like going on adventures or just having friendly chats.