I started to watch this drama because I like period dramas and I thought baduk at the centre of it might do for something refreshing, then I was captivated by the King's character, he was an all rounder and made for an interesting plot.

The king as a character and Jo Jung Suk's performance is what carried this drama for me and the reason it has the rating I give it, without him this drama would be so much worse, and if I had to rate the drama based only on him as a character it would get a 10. He's a very complete character and very engaging. It's such a shame that with such an amazing character and performance the rest of it was quite disappointing, especially anything involving the FL.

I like Shin Sae Kyeong and she has been the FL in a couple of dramas I rate very highly and I very much enjoyed. But being realistic I do think that she doesn't have a big range of acting skills and the roles she performs the best are those in which, I feel, she's playing characters that fit with her personality as a person or that she feels comfortable playing. Probably that's kind of the same reason why they took her for this one as the FL in this drama does share certain similar traits with characters she has played in the past. But there are a few things of her acting here that bugged me a lot, like the over stiffness and the constant eye moving to express what the rest of her face is not expressing. While I've seen her do this in other roles here it was very amplified. I don't know whether that was all her or the director was going for that and asked her to overuse it but at some point it started getting old and quite annoying.

Romance is also impacted by all this. ML is there, and his words and actions are clear and well acted and you feel the angst and the longing and all the feels. FL's on the other hand is just not there. So I enjoyed the romance part of this show, like everything else, because of ML, but it could have been so much better if FL had been at the same level.

When it comes to the writing I don't understand how we have such a good character in the king and such a miss in her. Most of the drama is just her contradicting the premise of her personality. She's supposed to be very intelligent, strategic and clever but she keeps making mistakes and becoming the damsel in distress.
The whole revenge plot was just plain BAD WRITING. She kept reaching bad conclusions, she kept asking the wrong questions, or not asking them and kept screwing everything up. Now, I could believe this as plausible and that a character like that can exist if the character hadn't been introduced as the opposite of that, and on the other hand if it was her alone it would have been more plausible, not with other people blindly involved in the revenge like it was the best plan and course of action.

Myung Ha was also quite frustrating and his whole plotline was quite pointless. It's dragged out for the sake of it by just making him not actively seeking information and justice but doing in a slow, second-hand way. Most of the drama he's annoying and towards the end he's just ok because by mellowing his personality they made him look ok now and made you forget all the things he did and said in the past and reduce it all to him being concerned about the Crown Prince. Disappointing.
Equally annoying was Lady Dong, although in this case her character was well developed and the actress did a good job at being the annoying piece of work she is. However, it was disappointing they were trying to make me like her at the end somehow, like if her behaviour was justified because she loved the king.

The rest of characters are basically background, they're ok, nothing to throw fireworks about except the kid that played the Crown Prince, he was great.
The queen dowager was always there but her arch was pretty anti-climactic in the end, nothing happened to her not it escalated much in any manner that would be interesting or significant enough for the plot.
Oh, and I almost forgot, special mention to Ja Geun Nyun (FL character's servant), she was annoying as hell, especially in the first half of the drama.

The end was a bit confusing (between the "I go, I don't go") and generally disappointing, and the last episode feels dragged and like they didn't know how to end it, like a kid dragging his feet leaving the park because he doesn't want to go back home. I definitely expected a bit more and a different ending. After all we saw in the drama I thought we deserved a better one for sure.
I'm also getting very tired of the time jump/one of main leads leaving just before ending it. It's been such a long time I haven't seen a drama where it felt justified to include something like this, especially not in the last episode when it's going to be resolved quickly and in an anticlimactic way. There was absolutely no point in making her go to the Qing, her father doesn't appear again and it's only there so they can meet in that tree to play baduk, what was also such a gamble she left the path/stopped for a break exactly there. There were so many options to end the story in a better way but it feels they chose the quickest to film and the laziest plot wise. Definitely could have been better and leaves a sour taste in my mouth.

Overall I think this show is watchable mainly for the king as a character and Jo Jung Suk's performance but that's pretty much it, plot is generally average for a period drama apart from the king, and the revenge subplot is very bad writing.
I think this show had a lot of potential but I don't think it was exploited as good as it could have. The plots could have been a lot more epic or more engaging, more than a classic hide and seek between hero and villain. The romance could have been so much better as well if we had had a better performance of FL and more moments to explore it.
I think the king is a character worth watching, it's just a shame everything else in this drama needs to be watched as well just to get that, so I'm happy I watched this show for the enjoyment I got of that character but a shame it's attached to many other things I didn't enjoy and wouldn't want to rewatch.