Yes. You and 3 other people can play online all using the same xbox. Just how you sign in for split screen games, do that for the live game. There is only one catch. If you want to play a RANKED game, each of you will need to have your own xbox live gamertage (gold membership). If you just want to play online on the social matches, then you can all join as your gamertag (suggesting that it has gold live) and play as a "guest" under your name. Just at the screen where you decide on which playlist, when you can see your name (pregame lobby), have them turn on a controller and select the gamertag they will be playing under.