Merlin Headcanons

Regent

There was a reason Arthur liked being regent.

If he wanted to kiss Gwen, he could do it without worrying about her being carted away for witchcraft.

If something went wrong in the court, he didn't have to blame it on sorcery unless he was absolutely certain about it, and he didn't have to worry about Merlin or Gwen being arrested for it.

(Merlin and Arthur went on a hunting trip once. Merlin had woken up with a muffled scream while Arthur was on watch. He'd looked down, embarrassed, and admitted in a hurried mutter that he had nightmares about being burned at the stake. It was clear he expected Arthur to laugh at him.

Arthur didn't laugh. He had nightmares about Merlin being burned at the stake too.)

If Merlin went missing - of course he went missing, he was Merlin - he could send as many patrols out to look as he liked and go looking himself until his horse was nearly ready to collapse.

If Gwaine mouthed off to a noble, Arthur could ask him why instead of banishing him. If he had a good reason ("He was throwing knives at Merlin!"), then he could react in an appropriate manner. (He invited the noble to train with the knights for the day. He made sure Gwaine spread the word before time. It was a miracle the noble was capable of crawling off the field. All injuries had been accidental, of course.)

If, for reasons that had everything to do with the fact that he was prince regent now and nothing to do with said previous incident, he didn't want Merlin serving visiting nobles anymore, that was his choice and right.

Arthur wanted more than anything for his father to make a full recovery. But he had to admit, when Merlin drank some poison meant for him, it was a relief to be able to get the antidote to him without being arrested.