As its name suggests, Sword Art Online centers on a fictional massively multiplayer online roleplaying game dubbed "ALfheim Online." Despite its faux-MMO roots, Lost Song is described as an action-RPG that borrows the series' familiar characters for an offline adventure. Not much is known of Lost Song at the moment, but Siliconera reports that it will feature a wholly new plot created specifically for the game.
There's currently no word on whether Sword Art Online: Lost Song will be released outside of Japan, or if the game will remain exclusive to its native country. Given the anime's burgeoning international popularity, it's quite possible it could be localized for Western audiences, but nothing is certain until Bandai Namco unveils official launch plans.
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