A few things you need to know. You MUST know how to fill a position. In order to be a good back player if you see somebody on your team get shot like your snake you dont think twice about filling You run and take their position or a position that would better the field layout with 1 less man. You must also be able to lane well off the break. By laning you stand the chance of gaining the upperhand right off the bat by shooting their guys so pick smart lanes and if need be hold it for awhile. Communication is also something very important. On our team communication is worked by you constantly yell what you see and you yell what you hear from what your teammates tell you. So on our team if I yell something my players repeat it. Another thing you must be able to do is Run and gun. This skill is crucial especially when your filling. You dont need it but to be a good back you do. Be able to shoot in the oppisite team while you run helps alot when trying to fill to 50 or so. One last thing that you NEED to know how to do is a good run by. You need to be able to close that game as fast as possible as time may be running slim and you and your team need to be able to kill those last couple guys in 30 seconds or less. So you want to try and keep a g count with numbers 1,2,3,4,5 so as soon as we hear G 4 we start closing the game. So i don't know pick and choose what you want from this but thats what i believe you need to be a good back player.