The upcoming issue of Dengeki PlayStation, leaked by Hachima Kikou has revealed that upcoming crossover Accel World vs. Sword Art Online: Millennium Twilight will take place within the same world as Sword Art Online: Lost Song.

Called “ALfheim Online", players will be allowed to move freely about in 360 degrees as they did in the latter title. A "GS (Ground-Sky) Active Change Battle” system will be used, where players will be able to switch between characters in a three-person party and attack enemies in real time on both land and sky.

More plot details were revealed as well. An emergency maintenance occurs in ALfheim Online while Kirito and his friends are adventuring. As Yui inexplicably runs off and he tries to catch up to her, Kirito is assaulted by a mysterious dark machine avatar that goes by the name “Black Lotus.”

Bandai Namco launched the first trailer for Accel World vs. Sword Art Online back in October, teasing a few scenes of author Reki Kawahara’s two universes in the new cross over game, starring fan favorite characters Kuroyukihime and Kirito.

A live stream for the game is set for December 7.