Obviously, the King Beyond the Wall himself is a central character. He's often depicted as a strong and fearless leader. Then there are the wildlings who follow him. Characters like Ygritte are also quite common, as she was an important figure among the wildlings in the original series. And sometimes, characters from the Night's Watch get involved too, as they are in direct conflict or potential alliance with the King Beyond the Wall.
In many fanfictions, there could be new characters created specifically for the story. For instance, a mysterious figure who has the ability to communicate with the White Walkers and tries to broker peace between them and the King Beyond the Wall. But of course, the mainstay characters from the original 'Game of Thrones' lore like Jon Snow might also play a role, especially considering his connection to the North and the wildlings.
Daenerys Targaryen also appears frequently. In some fanfictions, she might be a key figure in helping the good king, perhaps through her military might or her experience in dealing with different cultures. Her dragons can also add an exciting element to the story.
Obviously, the Dragon King himself is a main character. He is usually depicted as a powerful and complex figure, with his own goals and desires for the kingdoms. Daenerys Targaryen is also often present, either as an ally or a rival to the Dragon King, given her own connection to dragons in the original series.
In some fanfictions, the King Beyond the Wall might discover a long - lost magic that gives him an edge. Maybe he finds a way to control the harsh winter, using it as a weapon against his enemies rather than just enduring it. This would completely change the nature of the conflict in the story.
Arya Stark is also a common character paired with the Winter King in fanfiction. Arya's skills as an assassin could be useful to the Winter King's cause. She might be sent on secret missions by him or they could form a bond over protecting the innocent in the North.
Well, the Lord Beyond the Wall might be a figure who has been there since the dawn of time in the fanfic's version of the 'Game of Thrones' universe. Maybe he's a spirit or a long - lost hero who has turned into something more due to the magic and harshness of the far north. He could be a force that both the Night's Watch and the wildlings fear or revere, depending on how the story in the fanfic unfolds.
Percy Jackson himself is often a central character. Given his connection to the sea and his heroic status in the original series, he's likely to be involved in any story related to the primordial thrones. He might be on a quest to understand or protect the thrones.
Well, the Gold King is obviously one of the main characters. There might also be his advisers, like an old and wise man who has been with him since his early days. His enemies are also important characters, perhaps a rival king or a powerful sorcerer who wants to dethrone him.
Obviously, Harry Potter is the central character. But other characters like Hermione and Ron are often involved too. They might have different reactions to Harry's new 'King of Darkness' persona. Dumbledore could also be a major character, as he might try to guide Harry or figure out how to deal with this new development. Voldemort could also play a significant role, perhaps seeing Harry as a more formidable opponent or a potential ally in his own dark schemes.
Harry Potter himself is often involved. He might be coaxed into playing the drinking game by Ron and Hermione. Ron, with his love for a good time and food, would be really into the idea of a drinking game. Hermione, on the other hand, might be initially reluctant but then get caught up in the fun.
In some cases, the Mountain might be paired with other powerful warriors from different regions in fanfiction. For example, a character from Essos who has a unique fighting style. This could lead to some epic battles and exchanges of combat techniques in the fanfiction.