I hate that fucking game. Especially the single player. The AI is so unbelievably idiotic. "Oh look! The player is coming at me with a shotgun! Well theres only one smart thing to do in a situation like this. I´ll try to run through that wall! Ooops. Didnt work. Well, if I keep trying it will work sooner or later."
And they cant see you until your like 2 feet away from them.