Kingdom Hearts is known throughout its fanbase as a mind-bendingly complicated series with games released out of order, layers upon layers of mystery, and the oh-so-helpful inclusion of time travel. Keeping track of who's who and why some people even exist can require spreadsheets and diagrams, timelines, and YouTube recap videos — and that's not even getting into the esoteric systems that go into the gameplay.

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With that in mind, there are probably a lot of things that fans will miss on their first playthrough of the games. When taking a look back over the series, there will be some "a-ha" moments that stand out and make the players feel impressed at the forethought, or bitter at the realization that the answer was staring them in the face the whole time.

Updated September 13th, 2022 by Hilton Webster: Kingdom Hearts, being so closely associated with both Disney and Final Fantasy, is one of those series that never quite loses its popularity, and with plenty more games on the horizon that isn't likely to change. The story can be a bit dense to get into though, even for experienced players.

14 Organization XIII And True Organization XIII

Xemnas, Xigbar, Terra-Xehanort and Roxas in Kingdom Hearts 3

Originally introduced in Chain of Memories and gaining the spotlight in KH2, Organization XIII has been the villainous face of the series for over a decade, originally headed by the sultry-voiced Xemnas. Those black cloaks and a wonderful variety of characters were a highlight of the series, though its members had a tendency to swap around a bit.

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Kingdom Hearts is never so simple though. You see, in Dream Drop Distance they introduce the Real Organization XIII. This organization is the true one formed by Xehanort with the ultimate goal of eventually convening to rejoin all his pieces, so he could reform himself in the present time. The former organization was just a fill-in until the time was right for the true members to emerge. Nomura definitely thought this through.

13 All Of The Time Travel Story

Riku and Young Xehanort facing each other before their final battle begins

Beginning with Kingdom Hearts 2, the story takes a few more leaps than previous entries. The Heartless are suddenly joined by Nobodies, the separated heart and body of an individual. Kingdom Hearts is being summoned again, now by people without hearts. Riku has conjoined with Ansem. That's all nothing compared to the time travel.

Dream Drop Distance adds a lot to the story here, including Young Xehanort. In simple terms, a person can travel through time, provided some part of themselves actually exists there. So in his youth, Xehanort split himself, so he could accomplish many deeds across many times, irrespective of time itself. The events never occurring in chronological order can make it a bit tough to piece the logic together.

12 Organization XIII's Names

Axel saying "Got it memorized?" in Kingdom Hearts 3.

Organization XIII is one of Sora's dogged pursuers for the majority of the Kingdom Hearts games - their goals always seem to conflict with Sora's, and they make for some of the most exciting boss fights. Each member of the Organization has quite an odd name - a seemingly random jumble of letters, all of them including an 'X.'

This is by design, and you only realize this once you've played the games fully. Each nobody in Organization XIII is given a new name upon their awakening, and this is made by shuffling around the letters in the names they had when they were alive and adding an 'X' into the mix. Knowing this ahead of time would be a great clue as to Roxas' true identity!

11 Why Does Verum Rex Look So Realistic?

Kingdom Hearts 3 Sora fighting Yozora above Shibuya Crossing in the Quadratum world

Playing through Kingdom Hearts 3 can be a dazzling experience, and one moment that might give you pause for thought is encountering the Verum Rex game in Toy Box. This part of the game features a far more realistic art style than we're used to, and Re:Mind shows the world of Quadratum off in greater detail.

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From what little we know of Kingdom Hearts 4 at the moment, we know that Quadratum is a world unlike any other, on a separate plane of existence to the one we're used to. It's implied that it's something of an afterlife, as it's where Sora ends up after the end of KH3. Hopefully we'll solve all of this curious location's secrets in the next game.

10 Why Does Roxas Look Like Ventus?

Kingdom Hearts Roxas Ventus

Playing Kingdom Hearts 2 and Birth By Sleep in any order is bound to make any player ask this question; the two Keyblade wielders look eerily similar and are even both voiced by Jesse McCartney. The mystery as to why they look identical can really only be unraveled by playing both games. It is revealed in Birth By Sleep that Sora took Ventus's heart inside of him after the process of removing the darkness from his heart left him comatose.

Fast-forward to the climax of Kingdom Hearts 1 and Sora uses the Keyblade to wake Kairi up from his heart, releasing both of their hearts and creating Roxas as a result. As Ventus's heart had no body to go to, it went with Sora's body to create Roxas. This explains how Roxas can be Sora's Nobody without actually looking like Sora — Roxas takes on Ventus's heart and appearance wholesale.

9 Castle Oblivion And Organization XIII

Kingdom Hearts Castle Oblivion location

Kingdom Hearts: Chain of Memories (and its remake for the Playstation 2) can be quite a confusing entry in the series if the player is coming straight from the original without any further knowledge. Castle Oblivion is full of hooded figures who like to speak in riddles and speak of plans that get revealed only in a piecemeal way.

Once the player has completed Kingdom Hearts 2 and Kingdom Hearts 358/2 Days the story makes a lot more sense as those games help to explain the Organization's goals. Players will know the Organization members more and recognize each step and misstep made in their plans.

8 Dual-Wielding Keyblades?

Kingdom Hearts Roxas Dual Wielding Oathkeeper and Oblivion Keyblades

Having the power of two wielders inside them seems to make it possible for a Keyblade wielder to use two weapons at once. Acquiring the ability to dual-wield may seem to be a simple powerup in Kingdom Hearts 2 for both Sora and Roxas, but it's a significant clue.

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Being a Keyblade wielder, Sora has the heart of another Keyblade wielder (Ventus) inside him. This is transferred to Roxas while he's alive, as Ventus goes with him. The fact that dual-wielding seems to be a temporary powerup may be a reference to how Ventus still needs to recover from his ordeal.

7 The Darkness Of Kingdom Hearts

Riku from Kingdom Hearts In The Dark Realm looking at his old sword

At first, the original Kingdom Hearts really seems to be a low-stakes game filled with cool Final Fantasy and Disney characters. One would be forgiven for thinking that it's a 'kiddy game' with some odd dark narrative choices. For example, the implied apocalypses in the disappearing stars that led to the 99 Dalmatians and summon stones being scattered across the game seem like a really odd turn for what should be a lighthearted game.

Playing the sequels really drums in how moody the franchise is, with truly dark villains and a backstory involving a catastrophic war. At that point, players will barely bat an eyelid at the doom and gloom.

6 The Unknown Boss Battle

Kingdom Hearts The Unknown Mysterious Figure Secret Boss

In Kingdom Hearts: Birth by Sleep the player can fight a superboss known as 'the Unknown.' He's a terrifyingly tough fight that will test the player's knowledge and mastery of the combat system. As a character though, he is just a mysterious figure in one of Kingdom Hearts' iconic black trenchcoats.

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It is only in Kingdom Hearts Dream Drop Distance and Kingdom Hearts 3 that the identity of The Unknown becomes clear. He is Young Xehanort, traveling through time to collect vessels for the Real Organization XIII. Why he chooses to fight the trio is a mystery. Perhaps he wished to test his skills?

5 The Nameless Star

Kingdom hearts nameless star sora the final world cutscene

At the end of Kingdom Hearts 3, Sora meets the Nameless Star at the Final World. Her identity and true importance are currently unknown but there are clues to be found upon replaying the games.

Kingdom Hearts Melody of Memory makes the biggest reveal with the Fairy Godmother telling the heroes that the Nameless Star is one of the people needed to find Sora, who disappeared at the end of Kingdom Hearts 3. This may provide more significance to their meeting at the Final World and should hopefully be something we find resolved during Kingdom Hearts 4, which takes place Quadratum.

4 The Robed Figure On Destiny Islands

Kingdom Hearts Robed Figure Cutscene Xehanort

While Kingdom Hearts makes it plain that the Robed Figure who appears in the prologue of the game is Ansem, Seeker of Darkness, it takes a different game to explain his origin and why he looks like he does. The Robed Figure's origin is in Xehanort, going by the name of Ansem, traveling back in time as part of the plan revealed to the player in Kingdom Hearts Dream Drop Distance.

As he gave up his physical form willingly, his Heartless managed to keep his selfhood but did not gain a normal appearance, instead becoming the Robed Figure. This was all changed when the Heartless was able to possess Riku and become the form that Sora fights as a final boss.

3 Xion Is A Vessel

Kingdom Hearts Xion Xemnas split image vessel

In Kingdom Hearts 358/2 Days Xion makes her debut as an imperfect replica of Sora made from his memories. In that game, Xemnas states that Xion is more worthy of being a vessel than Roxas. While this is up to interpretation within that game alone, playing further games makes it more obvious what Xemnas means.

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It is revealed in Kingdom Hearts Dream Drop Distance that Xehanort's master plan is to create 13 vessels for different instances of his heart. Taking this into account, it's plain that Xemnas is referring to Xion's potential as a member of the Real Organization XIII, something that is realized in Kingdom Hearts 3.

2 Nobodies And Emotion

Axel, Roxas and Xion eating Ice Cream in Twilight Town

While the first few games featuring them explain that Nobodies only show emotions through their memories of emotions from when they were human, another game offers an alternative theory.

Kingdom Hearts Dream Drop Distance reveals that Xemnas lied to the Nobodies in Organization XIII. He did this so that they would follow his plans to acquire Kingdom Hearts which he said would give them hearts. In reality, they all had hearts and emotions all along but had their emotions suppressed by Xemnas so that they would listen to him.

1 The Secret Lingering Will Boss Fight

Lingering Will stares down Sora in Kingdom Hearts 2: Final Mix

In Kingdom Hearts 2 Final Mix, Lingering Will is a boss fight that can be accessed from Disney Castle. A portal to the Keyblade Graveyard appears, and through it, Sora can fight this super-tough boss. Lingering Will drops cryptic hints to plot points that would be explored further in the series, as well as name-dropping Ventus, Aqua, and Xehanort.

Kingdom Hearts Birth by Sleep reveals that Lingering Will is a collection of Terra's thoughts and wishes trapped inside his armor. This explains why he has the knowledge revealed in Kingdom Hearts 2 and is retroactively a fun reference for players in the know.

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