It started off great, with Gods fighting ghosts using their special powers, with scenes in the underworld as well as in the human world. As the story goes on, some of the characters who were really present in the beginning kinda disappear for a long time, but not because they were dead or anything.
There's a love triangle, but everybody knows that deep down the girl couldn't care less about one of them, completely in love with the other one. So it's not really exciting. Actually, it's rather boring or distressfull because it's pointless.
Nonetheless, this and other things tend to make sense as the end approaches. We finally meet the villain behind it alll.
Also, the rhythm of the show is a bit too slow sometimes, but the ending paid off, surprisingly good!
So, if you like doramas with magic and sword fights, you might give it a go, but lower your expectations and linger on.