This show is seriously overrated. Probably because good shows are rare these days since they pump them out like in an assembly line. Don't get me wrong. It's a nice little show that you can watch. Maybe for the first 2 seasons before you get bored. But it is not by any means a 8.7 stars show. I hope people will realize that in the future. The only reason people watch it in the first place is because they are curious about the monsters and where they come from. It is the same concept as Attack on Titan. Your curiosity keeps you watching until you are involved in the show and can't stop watching it despite being bored. Soap operas work the same way which says a lot about the quality. I had no problem stopping because at one point you do not watch the episode slowly anymore. You just skip to the seemingly interesting parts to understand the main story because all the other stuff is heavily dull.

So yeah, most reviews are based on watching on season. This is a long term review.