Portal

I wouldn't rate this game under 9. I gave it 10 but there are different opinions and I am, myself, unsure about a 10.

If you want to learn game design and puzzle design, do play Portal and listen to all the developer commentary. It's a big lesson. Compared to Limbo I felt more challenged by Limbo than by Portal. Even though Portal is 3D, Limbo had harder to solve puzzles. The voice acting of Glados is just fantastic. It's amazing how they've done a character that is not human and does not have a human body, yet the acting is perfect. After you get out of the test chambers the game introduces a new atmosphere. There is darkness, machines, tubes, thriller like. It was one of the best experiences I've ever had. Not scary, more like suspiciousness because challenge after challenge I felt that I was close to something without knowing what.

There is something special, a life lesson that is unrelated to games, but I do see how it relates to Limbo and Portal. Nobody is born knowing everything. Nobody begins a career knowing everything. Portal and Limbo begin with trivial puzzles and this same idea applies to life itself. Things grow and envolve in their own pace and everything begins small and simple. Going back to what I said in the beginning of this post. You don't have to know a lot of design to begin a career. In fact, the less you know makes it better because there is more room to learn.