How would Merlin and Arthur understand the concepts in Harry Potter fanfiction?

They might be quite intrigued. Merlin, with his knowledge of magic, would likely compare the magic in the fanfiction to his own experiences. Arthur, on the other hand, might be a bit more confused at first but would gradually get into the story, especially if there were elements of heroism and adventure similar to his own quests.

Their relationship might start with distrust. Harry, like Arthur, may be wary of Draco, as Merlin, due to their past differences. But as they face common enemies, they begin to rely on each other. Draco's magic skills, similar to Merlin's, prove useful to Harry, and they gradually form a bond of friendship and mutual respect.

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.

One idea could be that Merlin, with all his ancient magic knowledge, reincarnated as Harry Potter would be able to quickly master spells at Hogwarts. He might even introduce some long - lost magic that was known in his previous life. For example, he could have a unique way of handling potions that was based on his experiences in Camelot.

Merlin might start by teaching Harry the basics of magic from a different perspective. Maybe he would show Harry how to draw magic from the very essence of nature. For example, instead of using a wand in the traditional way, he could teach Harry to use his hands and the energy around him.

It would become much more complex. They might start off being confused and a bit awkward around each other. But then, as they start to explore their feelings, they could become closer in a more intimate way. Their friendship would be transformed into something deeper, with a new level of understanding and trust.

Arthur might be initially shocked and confused. He's used to Merlin being in control. But then he might find it quite hilarious and start teasing Merlin about it.

Merlin might become even more protective of Arthur. Since Gwen is carrying Arthur's child, Merlin would see it as his duty to safeguard the future of Camelot. He could be more involved in Arthur's personal affairs, which might initially annoy Arthur but eventually he'd come to appreciate Merlin's concern.

One interesting concept could be the merging of magical systems. In the 'Harry Potter' series, there's Hogwarts magic, and in Arthurian legend, there's magic like Merlin's. In the fanfiction, perhaps spells from both worlds are combined. For example, a character might use a Hogwarts spell with an Arthurian incantation twist.

He might also get angry. Merlin has his own pride and after all he has done for Arthur, being insulted like this would make him furious. He could start yelling back at Arthur, listing all the times he has saved Arthur's life or the kingdom.