Really enjoyed this episode. The point being that Arthur struggled with his first real test as King by making dubious decisions and definately NOT acting like himself. I sensed he felt lost and unsure and that was the reason why he listened to all the bad advice Uncle Aggy was giving him.
He pushed his best friend away and I do believe this part of Arthur's and Merlin's friendship needed to be explored. It eventually made Arthur actually realise that Merlin DOES give him good advice and despite Arthur being so cruel to him and saying some unkind things to Merlin, Merlin decided to stay loyal.
Also his realtionship with his lover Guinevere was explored too. Despite his numerous promises of when he is king they can be together, he broke them with the aid of Uncle who convinced him he couldn't have both (Guinevere and the throne). I think as a prince he felt he had more freedom with his choices but soon realised that as a king it wasn't so easy. The breakup scene was hard to watch (both actors were brilliant especially Angel Coulby) however, just like with his friend Merlin, maybe it had to happen to make their relationship stronger.
Although this story was a serious one it did have it's comedy moments. I particularly laughed when Arthur actually saw the man he was to fight, his expression was priceless. Also poor Merlin tripping up pass the tent as he followed Arthur. Finally Arthur giving Guinevere those flowers from under his pillow and telling her he found them at the side of the road,lol.
All in all I really liked it and have re watched several times.