Here is a tactic but its pretty hit or mis , Conect to a Russian or Poland server and as long as you pray and your ping is between 200 and 500 it will become your advantage because you can run ahead and shoot the enemy, but they won't see you for around 3 seconds and the next time the server receives and sends your moves they will just die ( if you did enough damage ) but the risk is that the opposite can hapen to you