-Quitting the game.
-The cover picture
-Invisible enemy parts or sometimes whole enemies (flying guns).
-Getting stuck to a wall or fence so you have to restart the whole mission.
-Objects don´t appear at all or appear late.
-Friend AI doesn´t work at all.
-The sniper is pretty much useless because you can just use the machine-gun, which shoots almost as accurately as sniper.
Ok, I´ll stop there.
Just a final warning to everyone: Do NOT buy this game!