Just Cause 2 is the wild adventure that takes the sandbox genre to a whole new level and not only asks you to create havoc but encourages it like a drug dealer giving out free samples. Sadly this awesome game lacks official multiplayer support but that hasn’t stopped some fans making a multiplayer mod for the game which supports hundreds of players on a single map.
In the video below the server was playing host to 600 players at the same time and over the test weekend a total of 10,000 players took part and apparently saw a peak server load of over 1,300 players. You can get the mod here.
Just Cause 2 Multiplayer site: http://www.jc-mp.com/