"Quake 4 unlike Doom 3 and Halflife 2 offers a some of the most frantic gameplay seen in a while. You don't just run and shoot at everything possible, you really have to watch where you are going and always be on the look out especially from behind to make sure an enemy doesn't respawn right behind you. The A.I. is decent with the Strogg army being intelligent and at times setting up ambushes and at times you will notice that they seem to collaborate together and attack at the same time, even rushing you with a melee attack. The Boss battles are quite epic and give you a real challenge as you cant just go in with a shoot and strafe tactic you need to think about how you are going to take them on. I did notice that some of the Strogg troops were pretty cheap in that say when you are in a tank they will hovver about you so that you have no way of attacking them. When this happened it was just easier to back into a wall and start shooting which is quite tedious."