This is a great one person game. I love to play it before I fall asleep and got half way done and the next morning when I woke up, somehow I was able to figure it out and fixed it. It is funny. But, it has been like this for many days. I like the fact that it has many ways to get to the results. Great to play with on plane or anywhere you need something to fill your time. Best of all, there is no need to have electricity unlike internet games or Sony psp. It allows me to think things clearly at work after I played this game.