In fanfiction, if Uther finds out Merlin has magic, it could lead to Merlin's immediate arrest. Uther is known for his extreme hatred of magic in the Merlin series. He might see Merlin as a great threat and try to execute him, just as he has done with other magic - users.
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.
Uther might initially be shocked. He has always been so against magic, so he could be furious at first. He might feel betrayed by Merlin, whom he has known for a while.
One great aspect of Uther Pendragon and Merlin fanfiction is the exploration of their complex relationship. In the original series, Uther is often at odds with Merlin's magic, but in fanfiction, authors can reimagine their dynamic. For example, some stories might have Uther discover Merlin's magic earlier and instead of persecuting him, learn to accept it due to Merlin's selfless use of magic for the good of Camelot.
She could be shocked at first. After all, Merlin has been hiding his magic for so long. Maybe she feels a sense of betrayal initially, but then she might see an opportunity to have an ally in the world of magic.
One popular plot is that Arthur is initially shocked and angry when he discovers Merlin's magic, but then he gradually realizes how Merlin has been using it to protect him all along. For example, in some fanfictions, Merlin uses his magic to save Arthur from a seemingly impossible battle, and Arthur finally comes to terms with Merlin's powers and they become even closer friends, united in a new way to protect Camelot.
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.
One great Merlin Uther fanfiction is 'The King's Regret'. It delves into the complex relationship between Merlin and Uther. It shows how Uther might have reacted differently to Merlin's magic if he had known the truth earlier. Another is 'Uther's Hidden Affection', which explores a more emotional side of Uther towards Merlin, a side that was perhaps masked by his hatred for magic in the original series.