I bough that game a week ago and played a few chapters already. I was interested because it has game elements that I enjoy. You can discover the land around you, craft new stuff, advance your character, follow a storyline and many more. So what about the game.
In an opulent, post-apocalyptic world, where nature has recaptured the ruins of a forgotten civilization, small groups of people live as primitive tribes of hunters and collectors. Their mastery over the new wilderness has torn the machines - frightening mechanical creatures of unknown origin. You are playing Aloy, a young huntress in search of her fate amidst the remains of an ancient past. Since their birth, Aloy has learned to use their skill, cunning, and deadly security to hunt down the machines, protect themselves against rival tribes, and survive in the merciless wilderness.
On your journey, you will discover various ecotopes, tribal settlements and machine types as well as the mighty ruins of a forgotten era. Can you unravel the secrets that connect them and reveal the fate of humanity?
So much to a little advert 
The game really is enjoyable and you forget about the time while your advance Aloy to a powerful huntress, scout and explorer. You start with little Aloy who is grown by her father Rost. You learn something about her mother during you advance through the story. I wont spoil too much. Starting with little Aloy helps you to get known to the environment, you learn how to sneak and escape from the machines, you learn to use a bow to fight them. Yes a simple bow can bring down tons of mechanical machines. Aloy fell into hole and landed in one of the ancient ruins, where she found a kind of communicator, device which she can use to recon the walk paths of the creators as well as to inspect the environment and learn about the weakpoints from those creatures.
I have played a few hours already and have 15% maybe 20% discovered. I jumped onto the head of this huge walker called Longneck and have fought a really aggressive machine called Thunderjaw:
All in all the game has several hours waiting for you. Unfortunate there is no multiplayer available. Something I find nowadays could attract more players. However then different kind of characters would be needed, which is why the current story they tell with Aloy would not fit. And except a few fights you are more like a explorer or scout. The fighting can be really challenging and i had to revive and start again a few times fighting this Thunderjaw machine. But dont panic you get better equipment with the time so you have some nice weapons to damage those machines. You also learn to take over control on some of them, so you can use them as riding machines - which make traveling in this huge world a lot easier and shorter
Unfortunate it is PS4 exclusive, but anyway i thought to let you know about this game. Below an overview of the machines:
