This game is definitely underrated. Too many people have tried comparing it with Halo. The graphics are very good and the gameplay is excellent. The AI is good. Enemies will sometimes charge, sometimes retreat and will use available cover. Your teamates are mostly useless but will occasionally help out a little. You have the choice of playing (or replaying) each mission as any one of your teamates. The gameplay is mostly linear but there is enough freedom to attack a couple of different ways. The story is decent enough and the sounds are very good. Multiplayer is well done also. I find the game to be very addictive and, in fact, I'm playing it as much as Halo 2.