Kingdom Hearts Birth by Sleep
is an action role-playing video game developed and published by Square Enix in collaboration with Disney Interactive Studios for the PlayStation Portable, serving as the sixth installment in the Kingdom Hearts series. The game was released on UMD in Japan on January 9, 2010, in North America on September 7, 2010, and in PAL regions on September 10, 2010. An international version of the game titled Kingdom Hearts Birth by Sleep Final Mix was released in Japan in January 2011, featuring the changes made in the non-Japanese versions. A direct sequel, Kingdom Hearts 0.2: Birth by Sleep - A Fragmentary Passage, was released in January 2017 as a part of a bundle of games called Kingdom Hearts HD 2.8 Final Chapter Prologue. The game utilizes an overhauled battle system different from previous games in the series which features new elements. It is a prequel to the original Kingdom Hearts, taking place ten years before its events. 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 the Unversed. The player has access to the three characters' different scenarios when playing. Development of the game began in June 2005, with parts of the game Kingdom Hearts II Final Mix meant to hint at Birth by Sleep. The game was directed by Tetsuya Nomura and co-directed by Tai Yasue. Nomura has referred to the game as "Episode 0", as well as "Episode 0.1" following the release of Kingdom Hearts χ, stating that it is on the same scale and plays as large a role in the series as Kingdom Hearts and Kingdom Hearts II. The game has been well-received, selling 1.27 million copies worldwide as of November 2010, and received positive comments from video game publications. Critics praised the game's gameplay, graphics, music, and storyline, but criticized the level design and characters. A high definition version of the Final Mix edition was released for the PlayStation 3 in 2014, PlayStation 4 in 2017, Xbox One in February 2020, Windows in 2021, and Nintendo Switch as a part of the Kingdom Hearts HD 2.5 Remix collection. Gameplay Birth by Sleep is an action role-playing game with hack and slash elements that introduces a gameplay aspect to the series called the Command System. This system allows players to customize a Command Deck with techniques and abilities that they can perform at will, called Deck Commands. Performing ordinary attacks and Commands fills a gauge displayed above the Command Deck. When certain requirements are fulfilled and the gauge is full, the player's basic attack is changed to the "Surge" Command, which racks up powerful combos depending on the active Command Style. Filling the gauge a second time replaces the "Surge" Command with the more powerful "Storm" Command. Unlike previous games in the series, the game does not utilize Magic Points (MP) for spells or magic casting. It instead uses a system