There could be a period of adjustment. Arthur might be hesitant to fully embrace Merlin's magic, but Merlin's loyalty and the positive uses of his magic may gradually wear down Arthur's resistance. Over time, their relationship could transform into one of mutual respect and admiration, with Arthur not only accepting but also being proud of Merlin's magic abilities.
The relationship could become more equal. Before, Merlin was in a somewhat subservient position, but with his magic out in the open, he becomes more of an equal to Arthur. They can now fight side - by - side in a different way, with Merlin using his magic to complement Arthur's skills. This new dynamic can add a whole new layer of depth to their relationship.
Some fanfictions show Arthur becoming more dependent on Merlin's magic in certain situations. For instance, when facing a powerful enemy that can't be defeated by normal means. This changes the dynamic from just a king - servant relationship to more of a partnership. Merlin, on the other hand, might feel more confident in using his magic openly around Arthur, which also alters their interactions. They could have more equal conversations and decision - making processes.
It would likely become very strained. Arthur has been brought up to uphold his father's anti - magic stance. So, when Uther discovers Merlin's magic, Arthur might initially feel betrayed and distance himself from Merlin.
Well, Arthur's reaction can be complex. At first, he might be angry because Merlin has kept this big secret from him. However, as he thinks about all the times Merlin has saved his life with magic, he begins to see that magic isn't all bad. He may feel betrayed, but also grateful in a way.
For Merlin, there are both good and bad consequences. On the bad side, some of the more traditional and anti - magic people in Camelot might try to oppose him. However, since Arthur now knows, he has a powerful ally. Arthur can protect Merlin from those who would do him harm. Also, Merlin can now be more open about using his magic for the good of Camelot, which is a positive change.
In some versions of this type of fanfiction, Arthur's reaction is complex. He might be stunned into silence when he first finds out. His mind would be racing with thoughts about all the times Merlin has used his magic to save him or Camelot without his knowledge. After the shock subsides, he may have a heart - to - heart with Merlin. They would talk about the implications of the secret, and Arthur would likely start to view Merlin in a whole new light, as not just his servant but as a powerful ally with a great burden.
Arthur could also feel betrayed. He has trusted Merlin completely, and finding out about his magic might make him think that Merlin has been hiding something huge from him all this time. However, depending on how the fanfiction is written, he might eventually come to understand Merlin's reasons for secrecy.
In many fanfictions, Merlin's magic acts as a catalyst. For example, if Freya is in danger, Merlin uses his magic to protect her. This shows Arthur that there is more to the world of magic than he thought. It can make Arthur more accepting of Freya, who is often associated with magic. Sometimes, Merlin's magic also reveals secrets about Freya that Arthur needs to know, which either brings them closer or causes some initial friction as Arthur has to adjust to new revelations.
Merlin's magic can both strengthen and complicate their relationship. On one hand, his magic allows him to protect Arthur in ways others can't. For example, he can use magic to heal Arthur's wounds secretly. But on the other hand, Merlin has to hide his magic from Arthur in many fanfictions because of the laws against magic in Camelot. This secrecy can create tension, like when Arthur suspects something is different about Merlin but can't quite put his finger on it.
Often, Gwaine reacts with acceptance. He's not the type to shun Merlin just because of his magic. Instead, he'll likely embrace it as part of who Merlin is. He could say something like 'Merlin, your magic doesn't change a thing between us. You're still my friend.'
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.