A great Xbox game, and now a great PC game!
I'm not going to mindlessly praise this game, so please don't skip over because of the high rating I gave it. I'm not some mindless fanboy here to tell you this is the greatest game ever, it isn't. This will be an honest consideration of the game as a whole. First, the game has a good story. They went to some trouble to make it interesting and keep up the surprises. There is good transition and you meet the right mix of characters for a given situation. There isn't really a moment where you find yourself saying "How did these guy's just show up here?" There was only one or two missions I asked myself "Why am I doing this, it makes no sense." You get some good helper AI's which seem to use weapons and pick up new ones like you would rather than just using their starting weapons or using the same one forever. It's pretty realistic. The friendly AI has to be one of my biggest praises for this game. In general, they are actually useful in battles! This is a far cry from many games where your "helpers" just get in the way or shoot you in the back. As a nice touch, these AI even apologize in the rare instance they hit a friendly unit (like yourself) by mistake. They are even effective when they hop onboard a vehicle with you. A disappointment is you can't give AI units commands; it'd be nice to have more choice of who to replace with whom when one of the guys gets injured and a healthy one is available. Another thing I found astonishing is this is probably the first game I've played where you go to where a battle supposedly took place and there are weapons, bodies, etc. laying around like there was actually a battle. You get more of a fell that a conflict occurred there rather than just a random body here and there. The enemy AI is realistic too. The little guys will hang around the bigger ones for support and tend to get startled and run screaming if caught alone. On the other hand, the Covenant sometimes has a habit of just sitting in their area and waiting for you chasing you down would be more realistic behaviour, but maybe they figured it'd make it too hard on the player. I don't want to spoil anything, but if you like games where you can see two groups fighting and use the distraction to tip the tide and then waste the winner this is the game for you. You get a few chances to do that. Reminds me of the Max Payne II mob wars. To sum it up, the characters act realistically for the most part, there is pretty good voice acting, the graphics look sufficient and run fine, the friendly AI is helpful and not annoying like most games, the levels are sometimes repetitive but the outside ones are varied and imaginative, there aren't any really cheesy bits, and the vehicles rock. All this adds up to an enjoyable experience that is worth the very cheap price tag on it.