I recommend this drama to anyone who loves historical fantasies.
I don't recommend it to people who like mostly lovely bubbly romcoms.
What I didn't like:
- seasons.... lol so meaningless, why separate it into seasons... ><
-too many names at the begging might be overwhelming plus the first episode is hectic as it doesn't show "passed...years" every time they time-skip.
What i liked:
- the story. It's different from what we usually see so i like it.
- twists and turns.
-costumes
-scenery

Overall I liked this first half of the drama :) but the whole season is more like an intro. and the real stuff will start i guess in the second. the story is nice and it gets more and more interesting later. as I said it is more like an intro and it gets power mostly during the 6th episode. However many historical dramas (and not only) have long introductions that are necessary for us to learn about characters, so it was okay for me. I liked this first season. The only thing is left is for the second and especially the last to be great. because an ending can ruin a drama lol. the first season is nice though.

MYTHOLOGY:
This series are based on Korean mythology about Dangun, who is considered the founder of Koreans. you can read about him on the internet. It is set in Ancient Jeoson and about Korea's first nation and Bronze Age. The myth depicts a story how a Heaven's Son comes to Korean Peninsula and makes The First Kingdom. Because he was the second or third son and couldn't become the ruler of Heaven. He lands on Great White Mountain. Later a Tiger and Bear come to him and ask him to turn them into human. So he tells them to go and eat mugwort and garlic only during 100 days or something. The Tiger gives up in the middle. But the bear eat's it and becomes a woman. The bear woman and Heaven's son have a child, Dangun. Dangun becomes the first real ruler of korea. Actually people say that he symbolizes a human as he was born from meeting of a spirit and an animal. Also he symbolizes the start of Bronze age in Korea. later he goes into a mountain and his spirit rests there. Well there are several versions and in one of them the capital they make is called Asadal. To compare it to the drama Dangun must be the Aramun Haesseula in the drama. Nheantals are the tiger tribe and Sarams (which means literally "human/person" in Korean) are the bear tribe. As you can see in the first episode, Naeanthals come to the meeting with tiger fur, tiger skulls, and Sanung Niruha (at the time ruler of Sarams) wears a bear mask. So this drama took this myth about creation of Koreans and made a fantasy :)

I think the production team just made several mistakes and that's why got so much criticism and low ratings. maybe im wrong, this is just my opinion but:1. they made this show come out not long after GoT ended.... many fans fresh from GoT came to this and saw many similarities. However historical fantasies all have similar clothes and similar power struggle. This series are based on Korean mythology. 2. they overestimated viewers lol I think many were not ready to get a different-like kinda a bit European setting fantasy from Korea. And were just too used to that the Korea usually does historicals mostly in Jeoson or Georyo (and sometimes Silla).

So if you are interested in this genre, don't let these things stop you from trying :) watch till the 4th or 5th episode and then decide if you like it or not :)