This game is, by far, the best Hitman game I've ever played (second to Blood Money). You'll see/hear a lot of people complaining about how quickly you'll die, if shot at, or that you can't really assault rush any missions - that isn't how you're supposed to play. It's purely stealth, 100%. Another complaint people will have is the lack of missions. Each missions, if you take your time, will take awhile. There's tons to collect, explore, and discover in this game. It's truly a snadbox stealth game and definitely worth buying if you're a fan of stealth, or just gaming in general.
