It's one of the most original FPS that came out, won awards for its originality but it didn't sell that good.
The game consist on parkour and you will die a couple of times but the view and adreneline it's just awesome.
I know you wont like the next bit, but I love playing this game more than Skyrim. I may have more hours on Skyrim but the game feels to big, yes that's the point, but, this game when you are mid-air it's just beautiful and vivid.
PS: Skyrim it's also realy realy good but EA did something good, and we should appriciate this due to the things they are doing to us (The Sims 4 is worst than the 3 and we have to buy the stuff that was for free). Wait for the one thats comming up with a open world.