Zynga has closed the MySpace version of its Mafia Wars social game. Players of the MySpace version are being directed to Zynga’s MafiaWars.com if they wish to continue playing the game. At the time of its closure, Mafia Wars was the second most popular social game on the MySpace network with over 13 million registered users. Zynga still operates Zynga Poker on MySpace, but has already closed other games like YoVille and Fashion Wars. Zynga’s biggest games, CityVille and FarmVille, were never available on MySpace.