The game's premise is the origins of the series' hero and villain, Sora and Xehanort, and delves 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 Hikaru Utada.
In the Land of Departure, three Keyblade wielders and close friends—Terra, Aqua, and Ventus (more commonly known as Ven)—train to become Keyblade Masters under Master 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, Master Xehanort, disappears without a trace. Terra is sent to destroy the Unversed and find Xehanort, who had earlier encouraged him to embrace the darkness within 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 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 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 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 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, Xehanort kills Eraqus and tells Terra to go to the Keyblade Graveyard, leaving the Land of Departure to be captured into darkness. At Destiny Islands, Ven once again encounters Vanitas and learns of his hazy past: Ventus was once Xehanort's apprentice, but his heart was deemed too frail for 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' 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 Sentiment, 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 Master Eraqus's Keyblade and uses it to unlock the Chamber of Waking and create Castle Oblivion from the ruins. After leaving Ven in the chamber, Aqua goes to Radiant Garden where she encounters Xehanort still in Terra's body, but having lost some of his memories. Aqua then battles Xehanort, who after the fight 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 lost in the Realm of Darkness. Xehanort is discovered by Ansem the Wise, ruler of Radiant Garden, and goes on to become his apprentice. Ventus' wandering heart finds its way to young Sora, merging with the young boy's heart.
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' 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 while darkness threatens to swallow the worlds again, 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.
The secret ending opens with Terra and Xehanort standing in a black abyss. The two have a faint glow around them, as they are actually their hearts inside the new Terra-Xehanort, and are conversing. Master Xehanort wonders aloud how Terra can still remain there after being possessed. Terra responds that it is still his body and heart, and he will eventually expel Master Xehanort. Master Xehanort merely shrugs this off, convinced that Terra will not be able to counter the darkness as he could not handle his own, but Terra reveals that Master Eraqus is residing within him, and no matter what the cost, he will not stop fighting until he has foiled Master Xehanort. The elderly Keyblade Master shows no concern, and gleefully informs Terra that possessing him was merely one of many roads he may choose to take.
Image of their backs, preserved in memory.
The new Xehanort, now with longer hair, brown eyes, and a lab coat, is seen walking through the corridors of Ansem the Wise castle. Braig approaches him and attempts to start a conversation but finds himself completely rebuked. Shocked at his lacking response, Braig immediately deduces that the new Xehanort surely has lost all of his memories. Looking into Xehanort's eyes, he asks precariously if the man standing before him is actually Terra, but Xehanort still does not answer. Braig pats him on the back and states lightly that it doesn't matter, and that he's "got his back." As the two walk on, Ienzo and Ansem the Wise appear in the hall, holding hands and eating sea-salt ice cream. Just before they turn a corner, Ienzo stops, gaining his master's attention. Ienzo turns his head to see Braig and Xehanort walking away together behind them. Ansem also looks back thoughtfully at the backs of Xehanort and Braig.
Two who were never meant to meet
A hooded Ansem the Wise sits in the Dark Margin, wearing a Black coat. Aqua appears next to him, asks his name and how he ended up in the Dark Realm. Ansem remarks how rarely he has guests says it is his second time on these shores and explains that his memory has faded almost completely, "much like the first time," so he has difficulty recalling his past. Aqua sits next to him on the shore and states that she fell into the darkness and has been wandering for a long time, unable to find a way to her original world. Ansem asks why she wants to return, to which Aqua replies she promised she would be there for her friends. Hearing the word "friends," Ansem remembers he had once known a boy who was very similar to her, a boy who was loyal and true to his friends and traveled across the worlds to safeguard the Light.
Ansem explains to Aqua that the worlds were almost swallowed by Darkness multiple times, but they were always saved by that boy, wielding his Keyblade. Hearing this, Aqua asks if the boy's name happens to be Terra or Ventus. Ansem tells her that it is neither of them and explains further that it has been over a year since he had met the boy. He reflects aloud that through seeking vengeance he did many terrible things to the boy and his friends, causing so many people to suffer. He blames it on his conscience and the fact he has the heart of a researcher and reveals that as the boy slept, he hid his research data within him. Ansem realizes that the boy, whose heart is connected to so many others, could possibly open the door and save those who are suffering because of him, remarking that they are all waiting to be born anew from sleep. Aqua then requests the boy's name.
All the pieces lie where they fell
Naminé is seen in the White Room of the Old Mansion in Twilight Town, finishing a drawing of Sora on the Paopu Tree. She says Sora's name and the scene changes to Roxas, Xion, and Axel, who are sitting happily together on the Clock Tower with sea-salt ice cream and looking into the sunset. Roxas and Xion say Sora's name. Ventus is seen sitting asleep at the Land of Departure, where Terra appears next to him. Ven wakes up and the two say Sora's name while looking at a shooting star. Back at the Dark Margin, Aqua begins to cry tears of joy having heard the name of the little boy she met on Destiny Islands. She says Sora's name while looking to the moon on the horizon of the Realm of Darkness.
Where they wait for him...
Sora is then seen sitting on the Paopu tree on Destiny Islands, holding King Mickey's letter from the end of Kingdom Hearts II and Kingdom Hearts coded, with a look of determination on his face. Riku walks up to him from behind, asking if he has decided yet. Sora responds that he has. Kairi appears and Sora explains to her that he needs to venture out and help the people who need him because he is who he is now because of them. Kairi smiles and places her Lucky Charm in his hand and tells him, "See you soon."
Reconnect. Kingdom Hearts
Development of the game began in June 2005 and was originally plan 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 so as to make use of the PSP's functions such as co-operative and competitive multiplayer gameplay. The title of the game is based on the secret ending of Kingdom Hearts II and Kingdom Hearts II Final Mix, "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.
Data mining of the game's files has revealed that two worlds were cut during development based on The Sword and the Stone and The Jungle Book with the latter having gotten far enough in development that King Louie's throne room exists in an almost complete state.
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, new Famitsu scans revealed a revamped User Interface (having been revamped twice before) as well as new worlds after a lack of news for close to a year. It was also revealed that the official names for the new enemies were the Unversed. Nomura also confirmed in an interview that Kingdom Hearts Birth by Sleep 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 Kingdom Hearts Birth by Sleep demo would indeed 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 also revealed that they are still currently working on Aqua's outfit which has been 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 Kingdom Hearts Birth by Sleep. He revealed that he was currently designing the cover art for Kingdom Hearts Birth by Sleep as well as editing the staff rolls due to there being three main characters in Kingdom Hearts Birth by Sleep. He also revealed that they were editing the new opening movie for the game, though he did not mention if a new opening song would be used or a previous one would be re-used like with Kingdom Hearts 358/2 Days. He also noted that they were also editing the promotional video and commercials for the game at the time.
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 during the event was finally unveiled to the public on December 28, 2009 as part of an update to the official site. 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.
It is also a departure from previous movies, which had been concepts for the next game they conveyed, whereas this one plays an integral role in the story of the series. The teaser 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.
The game is divided into three separate scenarios, with each scenario surrounding an individual of the three main characters: Terra, Ventus and Aqua. The gameplay of each scenario differs based on the personalities and abilities of each character such as power, speed and magic. Players are able to choose which of the three scenarios to begin with and are able to switch to another scenario, midway through playing a scenario. Each character's story will take about fifteen hours, hence the total amount of gameplay hours would be forty-five hours (excluding deck-editing, retries, and countless other activities), making Kingdom Hearts Birth By Sleep the longest game in the series to date.
Kingdom Hearts Birth by Sleep features several new abilities, such as Deck Commands, Shotlocks, and Command Styles. Each is 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.
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.
It was nominated for the "Best of E3 Award" by IGN and received a very positive response.
It's been given an 8.5 Review rating by IGN.
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 is an enhanced remake of Kingdom Hearts: Birth By Sleep. Additional content in the games include several new bosses such as armored versions of Master Xehanort and Eraqus as well as a battle with Monstro and a new "Secret Episode" with Aqua traveling in the Realm of Darkness.
Despite Larxene being the first playable female character in the Kingdom Hearts series in Kingdom Hearts 358/2 Days multiplayer mode, Aqua is the first playable female character in the Kingdom Hearts series that is canon to the game's narrative.