Good Multiplayer.
In AMSG you play as the main badass character sarge, who is driven to kill the leader of the tan army, after he blew up the main green city.
The graphics are pretty good, but not spectacular. However the cool plastic blowing apart effect is really cool.
There are three modes: Story, Multiplayer, and Training. The whole story mode is very easy because to kill people all you have to do is aim at them (you can just hold on to a button to lock on to them) and hold down the shoot button. That's it. Other than setting bombs, that's all you do. However, the one and only thing that you should get this game for is the multiplayer mode. The ctf is a lot of fun if you can get all 4 people playing. The problem is, is with all the online games, and top quality local multiplayer games (Halo 3 is a good example) There really is no reason to buy this game at all if you have one of those games is there??
In the end AMSG isn't a great game, but if it's the only multiplayer experience you can scavenge, than it will serve you well.