The geese themselves would be obvious main characters. Each goose could have different traits, like one being the brave leader, another being the cautious one.
A mysterious figure that appears in the middle of the game could be a main character. This figure could be a wizard who has the power to change the rules of the game, and the story could be about how the players and geese deal with these sudden changes.
The players in the game could also be main characters. They could have backstories that influence how they play the game. For instance, a player who is really competitive because they are trying to win a bet with a friend. Their actions in the game would be driven by this motivation.
The village dog could be a main character too. It could be constantly chasing the goose or getting tricked by the goose into chasing its own tail. It might also have a soft side and end up befriending the goose in an unexpected turn of events.
The main character is the goose, of course. And there are various villagers like the gardener, the boy, the shopkeeper, etc. who interact with the goose.
The goose itself is obviously a very popular character as the main troublemaker. People often write about its mischievous antics in great detail.
The main characters are the princess, the false maid, and the king. The princess is the true heir who is wronged, the false maid is the one who betrays her, and the king is the authority figure in the story.
In 'a goose love story', the main characters are probably a pair of geese. They could be geese with different personalities. One might be more adventurous and the other more cautious. Their different traits would add depth to their relationship. For example, the adventurous goose might lead the way to new feeding grounds, while the cautious one would ensure their safety along the way. Their interactions and how they complement each other would be key elements of the story.
The goose girl herself is a main character. And then there's the king who plays an important role in the story.
The goose girl, who is a princess in disguise, is a main character. She is the victim of the false maid's treachery. The false maid herself is another important character. She steals the princess's identity and tries to live as the princess. And there are also the king and queen, who are part of the princess's true identity and story.
In the Golden Goose story, there is the special goose which is the central character as it has the unique ability to lay golden eggs. Then there are the villagers. They play an important role as they are the ones who find the goose, and later their actions driven by greed lead to the story's outcome.
One main character could be a genetically - enhanced human who has special abilities, like Arya Stark's skills in the original. She could be on a mission to avenge her family who were killed by a powerful space - faring clan. There could also be a powerful warlord from a distant star system, a bit like Ramsay Bolton, feared for his cruelty and thirst for power. The interactions between these diverse characters would drive the story forward in this space - based Game of Thrones fanfiction.
Voldemort could also be a main character in a different way. Instead of just being the villain, he could be a complex figure who is also in the 'game' for the master of death's power, but with his own motives and backstory that are explored more deeply in the fanfiction.