sentences:  The title of the game is based on "II Final Mix"s secret ending, "Birth by Sleep", a title which director Tetsuya Nomura developed as he wanted a phrase having "by" as well as to use an English title like previous games.Nomura has referred to the game as "Episode 0", saying that the game is on the same scale and plays as big an importance as "Kingdom Hearts" and "Kingdom Hearts II".Early during the game's development, Nomura already had various scenes in mind such as Terra's and Riku's conversation in order to explain the latter's ability in the original games.