Very CoD-like in mechanics (hit-scan, progession achievements/unlocks, etc), which makes it a simple FPS. Free to play as well, and there is hardly and pay to win aspect in this. Those looking for a quick shooter with whacky concepts, this is a viable option.

The atmosphere in this game is extremely haunting. Will definitely give the heart a rush during those short instances being chased. For every other moment not running away from some monster, you are asked to solve challanges. In other words: its a psychological game in seeing how one performs under stress, at least in my experinces with the game. Note that you can get custom stories for this game, so same engine but unique twists on mechanic and story. Most custom story are found through Desura.

For those who can run DirectX 11, then this game would look gorgeous (I actually never ran it in DirectX 9, but still it should be graphically amazing). The storyline is immersive and while attempting to play stealth (which I personally fail at), it took about 40 hours to complete the game (not including the DLC). Honestly, this game is worth its full retail price since there are numerous ways to play the game even though you are going to for the same goal.