One of the strongest additions to every Final Mix edition across the Kingdom Hearts series have been the secret bosses added to the end of each game. However, among these secret Final Mix bossesKingdom Hearts: Birth By Sleep introduced a whole new chapter in its rerelease, complete with a new boss fight in the form of Dark Hide.

This boss-level Heartless adds quite a bit to the Kingdom Hearts franchise, both in how it acts as the cap off to the first story segment to be added to any game in a Final Mix update, as well as continuation that leads into a future game. On top of everything it means for the series, it also acts as one of few showings of Heartless in Birth By Sleep, as well as the only unique enemy of this type in the whole game.

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Birth By Sleep's Few Heartless

Kingdom Hearts Birth By Sleep Tank Toppler

The entire Secret Episode added to Birth By Sleep Final Mix in the Japan-only rerelease and eventual HD remasters, is actually the first time that the series' iconic Heartless appear. Before this, the rest of the game had included Unversed enemies like Tank Toppler as the primary villains to chase down through each Disney world. So, when players first come across the Dark Hide, this is the first time that a proper Heartless boss has appeared, all the way at the end of the added finale.

In the lore, this acts as Aqua's first introduction to the Heartless, but for longtime fans of the series it acts as a return to form for the first game to replace the familiar enemy. This new method of designing enemies would eventually be repeated in Kingdom Hearts Dream Drop Distance where Nightmares and Dream Eaters like Tyranto Rex became the game's primary villains and companions. However, for Birth By Sleep, adding the original enemies back into the game, in the hands of the fan-favorite character, makes even simple Shadows stand out, let alone a massive beast like Dark Hide.

A Fragmentary Passage

Kingdom Hearts 2.8 Features Gameplay From KH 3 - Birth by Sleep 0.2 Aqua

The Secret Episode where Dark Hide comes from has a second name that would eventually be repurposed for a short addition that was later bundled with Kingdom Hearts 2.8 Final Chapter Prologue. This episode, both in the Birth By Sleep Final Mix and the later Kingdom Hearts HD remaster, is called A Fragmentary Passage, since it acts as an add-on in both cases more than as a standalone title. It's thanks to this naming convention that some fans have become easily confused as to where exactly enemies like Dark Hide and these sections of Aqua's journey fit into the release order.

Strange naming conventions aside, both parts of A Fragmentary Passage act as an important part of the series' lore, as this is the time leading up to Aqua being nearly lost to the Darkness. Considering how important that part of Aqua's backstory is to the overall narrative of Kingdom Hearts 3, this has become a pivotal moment in the series. However, while the Demon Tide/Tower might be the most notable enemy in the more recent of Aqua's dives into the Dark Realm, Dark Hide was the original enemy that showed the real gravity of her situation.

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Aqua's New Final Battle

kingdom hearts boss battles

Aqua quickly became a fan-favorite of the series, being the first genuine Keyblade Master that players would be able to control, as well as the first female character to be given a playable story. This in part is what has made players so excited to see Aqua train Kairi after Melody of Memory, giving fans another hint of more female representation in future games. That being said, its strange to note that Aqua has one of the least thrilling finales out of the three playable characters in Birth By Sleep.

While the Final Episode gave Aqua a proper final fight against Terra-Nort, the end of her main story is against Braig, another fan favorite character who has recently seen some added complexity. However, the Secret Episode continued to make good on Aqua's character by giving her a thrilling new fight to go up against with Dark Hide. The fight itself is difficult at the levels most players would likely be at after having just beat the game, and leads perfectly into Aqua's continued story in a different way than the more final way the original game sent her into the Dark Realm.

Kingdom Hearts: Birth By Sleep is available now for PC, PSP, PS3, PS4, PS5, Xbox One, and Xbox Series X/S.

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