Kingdom Hearts Birth by Sleep (キングダム ハーツ バース バイ スリープ, Kingudamu Hātsu Bāsu bai Surīpu?) is an
action roleplaying game developed and
published by
Square Enix for the
PlayStation Portable, serving as the sixth installment in the
Kingdom Hearts series. The game was released in Japan on January 9, 2010,
[5] in North America on September 7, 2010 and in Europe on September 10, 2010.
[6] However, it was not released for the
PSP Go.
Kingdom Hearts Birth by Sleep was also released with a limited edition
PSP-3000 as a bundle in Japan featuring designs from the
Kingdom Hearts series on its back.
[7] An
international version of the game titled
Kingdom Hearts Birth by Sleep Final Mix is set to be
released in Japan in the start of 2011 featuring the changes made in the overseas versions.
The game also utilizes an overhauled battle system different from previous games in the series with new elements such as the Command Board, Command System and Dimension Links added in. The game is a
prequel to the original
Kingdom Hearts, taking place ten years before. The game centers on the journeys of
Terra,
Aqua, and
Ventus, characters briefly featured in
Kingdom Hearts II, in their quest to locate the missing
Master Xehanort and protect the worlds from creatures known as Unversed.
Development of the game began in June 2005 with parts of the game
Kingdom Hearts II Final Mix meant to bring clues of
Birth by Sleep. Director
Tetsuya Nomura has referred to the game as "Episode 0"
[8] saying that the game is on the same scale and plays as big an importance as
Kingdom Hearts and
Kingdom Hearts II.
[9] The game has been well received, selling a large number of units in Japan shortly after its release, and receiving positive comments by video game publications.