Sword Art Online: Lost Song is an action RPG by Bandai Namco Games Inc. for the PlayStation 3 and Vita. The PlayStation 4 Port released on November 17th, 2015. Part of the Sword Art Online franchise, this game moves the action to the world of ALfheim Online. The story takes place after the events of the original SAO with many reappearing characters such as Leafa and Asuna.
A Sequel was announced on Oct 3rd, 2015 by Bandai Namco named Sword Art Online : Hollow Realization. It is stated to return to SAO's Aincrad and is slated for a 2016 release for both PlayStation 4 and PlayStation Vita.