Kingdom Hearts Birth by Sleep

Kingdom Hearts Birth by Sleep is the sixth game in the  series. It was originally created for the (PSP). The game's name is shared with the secret video at the end of Kingdom Hearts II Final Mix, "", which depicts a stylized version of a scene from the game. Kingdom Hearts Birth by Sleep was developed by the same team that created Kingdom Hearts Re:Chain of Memories.

The game serves as a prequel to the first game, taking place ten years before. The story focuses primarily on Terra, Aqua and Ventus, three young Keybearers from before Sora's generation, although the game also gives focus to the origins of Sora and Xehanort, delving deep into the mysteries of Xehanort's bleak past and forgotten memories as well as how Sora and Riku came to wield the Keyblade in the first place.

Like Kingdom Hearts and Kingdom Hearts Chain of Memories, the main theme song for the game is "Simple and Clean", performed by. The Western releases include a number of new features, including the Sticker Album, a new boss, new Keyblades, abilities, mini-game maps and songs, and the addition of Critical Mode.

Chronologically, it is the fourth game in the timeline after Kingdom Hearts χ, Kingdom Hearts χ Back Cover and Kingdom Hearts Dark Road, taking place before , as well as partially overlapping with Kingdom Hearts 0.2 Birth by Sleep -A fragmentary passage-.

In September 2010, the Final Mix version was announced in Japan, which features the new additions from the North American and European versions, as well as additional extras. Aside from the PSP, the Final Mix version has also been ported to the PlayStation 3, PlayStation 4, and Xbox One.

Development
Development of the game began in June 2005 and was originally intended for the PlayStation 2 with Sora as the prototype protagonist of the game. Birth by Sleep was developed by Square Enix's fifth Product Development Division, based in Osaka, the same team behind Kingdom Hearts Re:Chain of Memories, and uses the same graphical engine as Crisis Core: Final Fantasy VII. During development of Kingdom Hearts II, the Osaka-based team had requested to be involved in a spin-off if one were to be made.

Development of the game began before the release of Kingdom Hearts II Final Mix. The plot was completed, but development was halted six months after it began due to development of Kingdom Hearts Re:Chain of Memories. The development team changed the platform to the PlayStation Portable to make use of the PSP's functions such as co-operative and competitive multiplayer gameplay. The title of the game is based on Kingdom Hearts II ' s and Kingdom Hearts II Final Mix ' s secret ending, "Birth by Sleep", a title which Nomura developed as he wanted a phrase having "by" as well as to use an English title like previous games.

Kingdom Hearts Birth by Sleep was directed by Tetsuya Nomura and co-directed by Tai Yasue. In 2007, Nomura mentioned a desire to create a spin-off Kingdom Hearts game on a mobile platform and for it to feature gameplay slightly different than other titles in the series. It was announced alongside Kingdom Hearts 358/2 Days and Kingdom Hearts coded at the Tokyo Game Show on September 20, 2007, where a trailer was shown in a photo-prohibited theater. New trailers were shown at the 2008 Jump Festa in December 2007 and the DKΣ3713 Private party in August 2008—a playable demo was also available at DKΣ3713.

The June 5, 2009 issue of Famitsu covered an interview with Tetsuya Nomura, where he said that the game was, at the time, at the voice recording stage.

In August 2009, Famitsu revealed a revamped user interface (having been revamped twice before) as well as new worlds after a lack of news for almost a year. It was revealed that the official names for the new enemies were the Unversed. Nomura confirmed the game would contain a secret ending like in Kingdom Hearts and Kingdom Hearts II for the next game in the Kingdom Hearts series which he confirmed a main game and the one which Nomura stated would link up Kingdom Hearts Birth by Sleep, Kingdom Hearts 358/2 Days, and Kingdom Hearts coded. He also confirmed that a demo for Birth by Sleep would be playable at the 2009 Tokyo Games Show together with a new trailer.

In early October 2009, Square Enix released their Tokyo Game Show 2009 trailer to the public on the official website. Nomura revealed that the concept of the Command Board originated from when he was in elementary school as at that time he was very fascinated with board games and even made his own; hence he wanted to incorporate a fun board game into the game. He also revealed that the name Master Eraqus came from an anagram of Square, and said that both Master Eraqus and Vanitas would be voiced by voice actors who are very difficult to hire (Makio Inoue and Miyu Irino). He revealed the team were working on Aqua's outfit which was revamped three times to find a balance between too conservative or revealing. The official release date was also confirmed as being January 9, 2010.

In late October 2009, Nomura updated the official Kingdom Hearts blog, "Message from the Kingdom", with a status report about the game. He revealed he was designing the game's cover art as well as editing the staff rolls due to there being three main characters. He also revealed that they were editing the opening movie, promotional videos and commercials.

In December 2009, the game made its final public appearance before its Japanese release at Jump Festa 2010 on December 19, 2009, where a playable demo as well as new footage from the game were present and shown. The trailer shown was unveiled to the public on December 28, 2009, as a website update.

Like previous console titles in the series, the game contains a secret movie at the end, which had been described as being more like a "true ending" rather than a teaser for the future like previous ones. The movie is approximately thirteen minutes long, and is not pre-rendered like the previous movies. The movie features dialogue and shows characters that are present only during the movie. Development of the movie began in October where Nomura noted in the blog that the game would contain a teaser to the next major Kingdom Hearts game similar to the teasers Deep Dive and Birth by Sleep.

Story
Kingdom Hearts Birth by Sleep begins in the Land of Departure, where three Keyblade wielders and close friends—Terra, Aqua, and Ventus (more commonly known as Ven)—train to become Keyblade Masters under Eraqus. To achieve this rank, Keyblade Apprentices must take the Mark of Mastery exam once they come of age. Terra and Aqua take this test together, but while Aqua passes the test, Terra is deemed unfit to become a Keyblade Master due to the abundant darkness in his heart. Afterward, a group of mysterious creatures called the Unversed begin to surface in other worlds, and another Keyblade Master, Xehanort, disappears without a trace. Terra is sent to destroy the Unversed and find Master Xehanort, who had earlier encouraged him to embrace the darkness in his heart if he desires the strength to become a Keyblade Master. Ven, meanwhile, is goaded into following Terra by Xehanort's mysterious apprentice Vanitas, against Eraqus's wishes. Aqua is dispatched by Eraqus to survey Terra and keep him from falling into darkness, as well as to bring Ventus back to the Land of Departure.

Upon arriving in other worlds, Terra, Aqua, and Ventus encounter various Disney characters, new and old, fighting off hordes of Unversed along the way. Among the characters they meet is Mickey Mouse, apprentice of the sorcerer Yen Sid, who is also on a mission to destroy the Unversed. Terra ends up attracting the attention of several Disney villains, who offer him the whereabouts of Master Xehanort in exchange of assistance for their own dark agendas. Terra reasons that Master Xehanort is after the seven Princesses of Heart—maidens who lack darkness in their hearts—and encourages Aqua to help them strengthen the light in their hearts, hoping it will draw Master Xehanort out. However, Aqua and Ven grow increasingly concerned for Terra when they hear rumors of him committing sinister deeds throughout other worlds. The three briefly reunite at Radiant Garden, where Aqua meets Kairi, a young girl containing a strong and pure light in her heart, and helps strengthen her light. Aqua and Ven also confront Terra, who distances himself from them to keep them out of the way of his increasingly dangerous dark powers. Terra and Aqua try to convince Ven to return to the Land of Departure, but he refuses until he is certain Terra won't fall into darkness.

Terra and Aqua eventually find themselves at Destiny Islands, where they encounter two young boys, Sora and Riku. Terra sees potential within Riku and deems him worthy of one day wielding the Keyblade, while Aqua senses strong ties with Sora and Riku to Ven and Terra, respectively. Ven, meanwhile, comes across Master Xehanort, who reveals his intentions to use Ven's heart to create a final Keyblade known as the χ-blade, something Master Xehanort says Master Eraqus had known all along. Ven returns to the Land of Departure to confront Eraqus, who tries to erase Ven to prevent Master Xehanort's plans from succeeding. However, Terra, who had been sent there by Xehanort, misinterprets the situation and attacks Eraqus, teleporting Ven to safety. As soon as Terra realizes his error, Master Xehanort arrives and cruelly kills Eraqus and tells Terra to go to the Keyblade Graveyard, leaving the Land of Departure to be consumed by darkness. At Destiny Islands, Ven once again encounters Vanitas and learns of his hazy past: Ventus was once Master Xehanort's apprentice, but his heart was deemed too frail for Master Xehanort to use him as he intended, so he extracted the darkness in Ven's heart and used it to create Vanitas. As with Terra before him, Ven is instructed by Vanitas to go to the Keyblade Graveyard. Aqua, in the meantime, learns of Eraqus's death from Yen Sid, who tells her to go to the Keyblade Graveyard as well.

Terra, Aqua, and Ventus gather at the Keyblade Graveyard, where the remains of the mysterious Keyblade War are found. Master Xehanort appears with Vanitas and reveals his plan to use the χ-blade to unlock Kingdom Hearts and unleash the forbidden secrets of the Keyblade War onto the various worlds, as well as to use Terra's body as a new vessel for his own heart so that he may survive long enough to see his plans come to fruition. An epic battle ensues, with Xehanort freezing Ven, and Vanitas knocking Aqua unconscious. In his rage, Terra unleashes the darkness in his heart, inadvertently allowing Xehanort to unlock his own heart and successfully transfer it into Terra's body, which results in the birth of a new, younger Xehanort. However, Terra's mind continues to linger in his discarded suit of Armor, which comes to life and defeats Xehanort. Ven, meanwhile, manages to thaw himself before Vanitas can kill Aqua, and discovers his dark counterpart to be the source of all Unversed. Vanitas merges with Ven, possessing him and creating the χ-blade. Aqua awakens under Mickey's care, and the two fight the possessed Ventus while he battles Vanitas from within. Aqua shatters the χ-blade as Ven destroys Vanitas, bringing an end to the Unversed, though Ven's heart is lost in the process. The destroyed χ-blade unleashes a burst of light, which consumes everyone present and scatters them to the corridors of space, save for Terra's Lingering Will, which remains in the Keyblade Graveyard.

Mickey saves Aqua and Ventus and brings them to the Mysterious Tower, where Aqua learns that Ven has fallen into a deep sleep and will not awaken until his heart returns. Aqua brings Ven back to the ruins of the Land of Departure, where she discovers Eraqus's Keyblade, and uses it to lock the Chamber of Waking and reshape the world into Castle Oblivion. After leaving Ven within the Chamber, Aqua goes to Radiant Garden to battle Xehanort, who still inhabits Terra's body, but having lost some of his memories. After the fight, Xehanort attempts to unlock his heart, losing his memories completely in the process. Soon after, Terra's body starts sinking into darkness, but Aqua dives into the darkness and saves Terra from disappearing. Realizing her glider won't be able to make it back through the portal in time, Aqua sacrifices herself by discarding her armor and using it to guide her glider, Terra-Xehanort in tow, back through the portal leaving herself behind and falls into the Realm of Darkness.

Xehanort is discovered by Ansem the Wise, ruler of Radiant Garden, and goes on to become his apprentice. Ventus's wandering heart finds its way to young Sora, being absorbed into the boy's body. Meanwhile, Aqua walks along and is attacked by several Darksides. Initially, she draws Master Eraqus's keyblade, but upon seeing the number of Heartless, she decides to just allow them to destroy her. However, Aqua is saved by Terra and Ventus's Keyblades. Looking at her Wayfinder, she is then reminded of the people she's connected to. With renewed trust in her friends, Aqua continues on.

Blank Points
An unlockable secret ending shows the hearts of Terra and Master Xehanort lying dormant in Xehanort's body, waiting to see which will control it in the end, with Eraqus's heart revealed to be sealed within Terra's. It also shows a recovered Xehanort walking with Braig as Ansem the Wise and Ienzo pass by. Shortly after the end of Kingdom Hearts II, Aqua encounters Ansem the Wise in the Dark Margin. Ansem, who had survived the explosion of his Kingdom Hearts Encoder with few of his memories remaining, reveals to Aqua that although his quest for knowledge led to the ruination of many lives, hope lies in the form of Sora, who prepares to set out on another journey to help all of those whose hearts are connected to his.

Scenarios
The game is divided into three separate scenarios, with each scenario surrounding an individual of the three main characters: Terra, Ventus and Aqua. Players are able to choose which of the three scenarios to play at the start of a new game. The order does not matter, although Terra > Ventus > Aqua is often recommended because Terra is the slowest, and playing him after Ventus/Aqua can feel agonizingly slow. Aqua is often recommended last because she has one extra scenario (or two if playing the Final Mix version), in which the finale of the game concludes. Magic is extremely important in Aqua's scenario, and the player will need to spend time learning how the Melding system works and get an idea of what sort of outcomes exist. Because of the final scenario(s), the player should prepare Aqua as much as possible before doing the final boss in her scenario.

After finishing one character's scenario, the player should not save over their prior save when starting another, as the game is meant to be played with multiple save files, leaving the player with four save files in original version or five in the Final Mix version. This also holds true for having separate save files for Aqua's scenario, the Final Episode and Secret Episode.

The gameplay of each scenario differs based on the personalities and abilities of each character such as power, speed and magic. They are, for each character, roughly:


 * Terra: strong physical attacks, slow speed, poor magic
 * Ventus: medium physical attacks, strong speed, medium magic
 * Aqua: poor physical attacks, medium speed, strong magic

Once all three of the scenarios are completed and all Xehanort Reports are collected, the Final Episode is unlocked. In the Final Mix version, the Secret Episode is after the Final Episode.

Each character's story is usually around ten hours on average, hence the total amount of gameplay hours would be thirty hours for a basic playthrough, making Kingdom Hearts Birth By Sleep the longest game in the series to date. A completionist playthrough is much longer, as the game has plenty of extra activities.

Abilities
Kingdom Hearts Birth by Sleep features several new abilities, such as s, Shotlocks, and Command Styles. Each are triggered via the battle menu. Deck Commands are the standard abilities, equipped via the menu with a certain cool-down time similar to the deck system of Kingdom Hearts Re:Chain of Memories. Shotlocks are unique attacks that involve precise timing to unleash a dangerously powerful assault on an enemy. Command Styles are even more deadly abilities that are unique for Terra, Ventus, and Aqua, just like the Shotlock.

Command Board
Besides leveling up the normal way in the other games in the Kingdom Hearts series, players can also play on the Command Board, where they can land on special squares in a system similar to a game of Monopoly in order to gain special prizes, certain boxes summoning Disney characters or having other effects.

D-Link
Past Kingdom Hearts games have allowed the player to summon unique Disney or Final Fantasy characters to their sides, each with their own abilities and usually not encountered anywhere else in-game. Kingdom Hearts Birth by Sleep views this ability in a new light; summons are replaced with Dimension Links, shortened to D-Links, which grants the wielder the powers of a unique character for a short time. Wireless D-Links are also possible, allowing a player to connect with a friend's PSP to summon their character to the friend's side. D-Links have their own menu, and are each granted a special ability, summoned by selecting the command from the battle menu.

Multiplayer mode
Like its predecessor, Kingdom Hearts 358/2 Days, Kingdom Hearts Birth by Sleep contains a multiplayer mode known as Arena Mode. While only a differently colored armored form of Terra, Aqua, and Ventus are playable, new abilities are usable only through this mode, and players can obtain bonuses for use in Story Mode. Up to three players can battle Unversed with customized names. They will also be ranked, this rank demonstrated by colored symbols that look like those Terra, Aqua, and Ven wear. A new world known as the Mirage Arena is also only accessed via the Joint Struggle. You can also play on the Command Board in multiplayer mode with a specific Mirage Arena game board.

Reception
The game sold fairly well in Japan, as almost 500,000 copies were sold within two days of its release. As of February 14, 2010 the game has sold a total of 800,551 copies of the game solely in Japan.

The game has received the Gold Prize by Sony Computer Entertainment Japan for shipping more than 500,000 units in Japan.

It was nominated for the "Best of E3 Award" by IGN, and received a very positive response.

UK magazine rated Kingdom Hearts Birth by Sleep 3rd "Best on PSP" game revealed at E3 behind ' (also by Square-Enix) and ' in the September 2010 "E3 in 3D" edition (released July 2010).

IGN gave a 8.5 Review rating to the game, and Gametrailers also gave praise to the game, giving it a 9.2 in story, 9.3 in Design, 8.4 in gameplay, and 8.6 in presentation, with an overall rating of 8.8 out of 10.

Kingdom Hearts Birth by Sleep Final Mix
Kingdom Hearts Birth by Sleep Final Mix was announced in an issue of Famitsu Magazine. Players who purchased the first shipments of the game received an access code with it that, when inputted into the PSP game , unlocks 's Kingdom Hearts attire as an alternate outfit.

The Final Mix version has been ported to PlayStation 3 as part of the Kingdom Hearts HD 2.5 ReMIX, and to the PlayStation 4 as part of the Kingdom Hearts HD 1.5 + 2.5 ReMIX.