The Once Future King (смешанная)

Arthur dies, but it isn’t over: the Sidhe offer him an opportunity to make it right again. Since he’s in the lake of Avalon, he cannot be fully declared dead, it’s like he’s floating between the gates of life and death. But Death has touched him, it’s not in their power to send him back to life. They can, though, send him back in time, to the other time he has been touched by Death. From the bite of the Questing beast. Arthur accepts the offer, and he wakes up in his bed, seeing his father sleeping by his sickbed.
So I’ve seen fanfics where Merlin goes back, or when they both go back to the startline, but I just had the idea, what if it was Arthur burdened with the knowledge of the future, more than Merlin, because the poor boy deserves some break. And it was fun thinking about what decisions would Arthur make, if he had to do it all over again. For Arthur the Questing Beast was like five years ago or more, so he doesn’t fully remember everything, just main events. For example he remembers that the Lady Catrina was a troll, but he doesn’t remember that it was Cedric, who was possessed by Cornelius Sigan.
Also, English is not my first language, so sorry if I make mistakes! I hope you enjoy.