Honestly, that is the question that kept going through my mind the whole time I was watching the show. I thought it was a trick of the light at times, and other times it definitely looked like Doom's hair had changed color more than once. Sometimes it looked a mossy green, other times it looked a dark blue, and then would change to an almost black underneath with silver or gray mixed in. I suppose it helps emphasize his non-humanness, but I kept getting distracted by it every time I saw it.

Anyway, on to the actual review.
I'll be honest, a little over half way through the series, I took a break from it and then came back to finish it today and I tried to figure out why I needed to do that. Was I having burnout from all the dramas I've been watching? Possibly, but after coming back to it, I realized I was dragging myself to finish because I told myself I was going to watch something else after I did this one first. I think that says a lot.

I want to echo some things I read in other reviews, whereas this series has everything it should: great cast, good story, nice visuals,but a great soundtrack, but it still felt a bit flat. The cast were superb! I loved every one of them, and a special shout out to the guy that played Uncle Kevin, because he is the only foreign actor I have seen in a kdrama that isn't cringy and stiff in both his lines and acting.

I think the biggest problem with the series is the story. The premise is good and the beginning is intriguing, but where it comes up short is in the writing toward the middle to the end. The moments with the characters are good, but the rules about their situation seem unclear at times. Also, I thought the ending was very abrupt, but that's just me.