After watching this, I went outside and my yard looks less realistic than this demo.
This is basically 10 minutes of just walking around in what looks like, somehow, a relatively small area of Square Enix's Final Fantasy XV but oh my god is it beautiful. Nothing really happens at all gameplay wise, aside from the characters getting swiped at by a few monsters as they run past them. It's more or less a tech demo, just showing how open and beautiful the game is.
It's beautiful. So beautiful. I need to talk more about how beautiful it is, but I won't. You can see for yourself below.