On the Steam platform, HS2 is called SuddenStrike2:HiddenStrokeII or HiddenStrokeII for short. It is a 3D-like real-time strategy game with the background of World War II, and it belongs to one of the members of "Sudden Attack" series. HS2 is one of the popular online battle versions of this game in China, and the other version is called "Assault 1.2 1". On the Steam platform, the full name of this game is SuddenStrike2:HiddenStrokeII, and players will simply call it HS2.