In some cases, there might be new original characters created specifically for the fanfiction. These could be characters who have a connection to the ancient magic of Merlin and Morgana. For example, a mysterious wizard who has been guarding an artifact related to their power. They could initially be an enigma to Harry and his friends, but as the story progresses, they become an important part of the plot, either as an ally or an adversary.
Obviously, Harry Potter is a main character as the heir of Merlin. Hermione Granger is often included as she helps Harry figure out the implications of his new status and the mysteries that come with it. Ron Weasley might also be there, providing his usual loyalty and friendship.
Then there are the other members of the Black family, either alive or in portraits. They could be sources of information, guidance, or obstacles for the heir. For example, Walburga Black's portrait might be constantly berating the heir or trying to steer them in a more traditional, dark - leaning direction of the family's history.
The heir of the Black family is the key character, of course. But other characters like Hermione Granger could also be involved. She could help the heir with her vast knowledge of magic. And Dumbledore might also show up, as he has a deep understanding of the wizarding world and could offer advice or warnings to the heir.
Harry Potter himself is often a main character. Since it's a fanfiction related to his world, he might be the one to inherit something from Merlin. For example, he could inherit Merlin's wand or a special magical ability that Merlin had.
Well, of course, the heir of Morgana is likely to be a main character. They would be the focus as they navigate their new identity and the powers that come with it.
Well, a cool plotline might be the conflict it creates within the wizarding world. Since Merlin and Morgana have such complex and often opposing legacies in the lore. Harry, as their heir, could be caught in the middle of different factions. One side might see him as a great hope for a new era of magic, while the other could view him as a threat to the existing power balance. Also, his relationship with the Ministry of Magic could change drastically as they try to either control or use his newfound connection to Merlin and Morgana.
Dumbledore is often a main character in Harry Potter 1945 fanfiction. Since he was around during that time, many stories explore his youth, his friendships, and his early battles against the dark forces.
Obviously, Merlin is the central character. His character is the focus as he returns and the story usually revolves around his actions, decisions, and how he impacts the world around him again.
Well, of course, Harry Potter himself is often in these fanfictions. He might interact with the Hatter, perhaps being intrigued by the Hatter's strange hats and the magic they possess. Hermione Granger could also be a main character. She would be interested in studying the unique magic of the Hatter's creations and might even try to reverse - engineer them to understand how they work.
Harry Potter himself is often a main character. After all, it's a Harry Potter fanfiction. He is likely to be the one facing the challenges related to the mist.