What is so special with Horizon Zero Dawn that everyone is talking about it?

I understand Horizon Zero Dawn is the most sold game on PS4, by what is the fuss about it? What makes it so popular?

Well, Horizon Zero Dawn is just an amazing game. Right from the Environment, the robots, the other humans they all look good. Aloy looks nice and was animated pretty well. The robots are very detailed with multiple laters of weapons, armor, and synthetic muscles.