Gwaine is also well - liked. He can be the fun - loving friend in modern fanfiction, always getting Arthur and Merlin into (and out of) trouble, whether it's at a party or during some kind of modern - day quest.
Merlin is obviously the most popular. He's the main character and his magic and modern - day adventures are what drive most of the stories. His character is often adapted to fit modern scenarios, like having to deal with technology while still having his ancient magic.
Gwen also makes for an interesting character in fanfiction. She can be portrayed as a strong - willed woman who supports both Merlin and Arthur. In some stories, she might have a more active role in the magical side of things, perhaps even learning some magic herself to help protect Camelot.
Obviously, Merlin and Arthur are the main characters. Merlin, with his magical abilities and his role as Arthur's servant and friend. Arthur, the king who is destined for great things and has a complex relationship with Merlin.
Morgana can be a very interesting character in fanfiction. She has her own motives and powers, and in some fanfictions, she is explored more deeply, either as a villain with understandable reasons or even as a character who can be redeemed. Writers often play with her character, making her a favorite among those who like complex and morally ambiguous characters.
Guinevere is also a key character. Her intelligence and grace make her an important part of Camelot's court. In fanfiction, she can often be the voice of reason and compassion, especially when Arthur is being too headstrong.
Arthur himself is a very popular character to focus on. His journey from the human world to the Invisibles' world and how he adapts and grows is always interesting. Selenia is also a popular choice. Her strong - willed and adventurous nature can lead to many exciting storylines.
Merlin himself is extremely popular. After all, the fanfiction is centered around him. Arthur is also very popular as his relationship with Merlin is a major aspect of the original series and fanfictions often explore it further.
Nick Mallory is a very popular character to focus on. His journey and growth throughout the original story make him an interesting subject for fanfiction. You can explore his further adventures or what he might have been like before the events of the main story.
Obviously Merlin is a very popular choice. His magic and his role as the hidden protector of Arthur make him a central and interesting character. Writers can explore his inner struggles with his magic and his loyalty to Camelot.
Merlin would likely be seen as a bit of an enigma at Hogwarts. His magic is different from the norm, so he might be a bit of an outsider at first. But his kind heart and loyalty would soon win over his classmates. Arthur would be the brave and headstrong character, perhaps a bit like a Gryffindor version of his usual self. He'd be eager to learn about combat magic and would probably be a natural leader in group projects or Quidditch teams.