I haven't played Minecraft in well over a year but from what I can remember, they brought out some battle mode thingy which can have up to 8 players per battle.
However I remember it was awful as it was so damn laggy that it was basically unplayable. If you have played on a friends map with a maximum of 3 players, it lags extremely badly, mobs can hit you from like 10 blocks away and if you were to mine stuff, the drops wouldn't show up half the time.
So try taking 8 players and have them fight each other is so incredibly laggy.