What's the game about? does it have good combat design?
The game takes place in the 31st century, when large, animal-like machines roam the Earth, hunted by humans living in tribal communities. The world is set in the aftermath of an unknown cataclysmic event.
The story follows Aloy, a girl who grew up as an outcast with -- who I assume to be, though the story might say otherwise -- her guardian and tries to rejoin the nearby tribe to find out her past.
In terms of the combat, it's mainly a cat-and-mouse game with the large robotic animals in the wild. You can do stealth takedowns, kills with your spear or kills with your bow. There are also variations of bombs, bows and other slings to help lay traps. You harvest materials from the slain robots to trade for "shards" that'll get you better armor and weapons.
The game has a huge world and becomes open after the first couple of hours.
This is as far as I know from not reading any material and playing about three hours.
The PC game is a PS4 port, so take that what you will. It runs fine on my computer, but I won't be surprised if I encounter some kind of issue in the later game.
Should you buy it? It's up to you. I'd check out some LPs to get sense of the combat and see if the world and story appeals to you. I read many posts saying the story and character development are great, the lore is deep and the game rewards exploration.