Universes

The Universes, also called the World, is a term construct shown throughout all things. They are many worlds that fall into certain realms. All of these realms are on their own plane of existence. A Universe is also a term used to collectively refer to all the particular characters, stages, items, music, and other properties appearing in the tv, comcics, games, etc. that are thematically featured in another franchise.

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 * —About the Universe.

Travel
Travel between the worlds is normally impossible. The worlds are all protected by dimensional barriers that prevent outsiders from entering for the most part. However, these barriers can be broken, resulting in a meteor shower in that world.

In Kingdom Hearts and Kingdom Hearts II, Sora, Donald, and Goofy use the Gummi Ship to travel between worlds on the World Map, an event that serves as a mini-game between areas. Some worlds require certain special Gummi Blocks to access; for example, a special Navigation Gummi must be installed by Cid to unlock a second set of worlds in Kingdom Hearts. Once they reach them, the party can enter and then depart each world through its Save Points.

Three worlds can only be accessed by entering through other worlds and do not directly require use of a Gummi Ship
 * 100 Acre Wood via Pooh's book in Traverse Town (Kingdom Hearts) and Hollow Bastion/Radiant Garden (Kingdom Hearts II).
 * Timeless River via the Hall of the Cornerstone at Disney Castle.
 * Space Paranoids via Ansem's computer in Hollow Bastion/Radiant Garden.

It should be noted that in Kingdom Hearts: Chain of Memories, there are no Gummi Ships; the worlds Sora visits are recreations from his memories from the first game brought to life on each floor of Castle Oblivion. This is likewise true of Kingdom Hearts Re:coded, wherein all worlds are recreations of data from Jiminy's Journal.

There are also no Gummi ships in Kingdom Hearts 3D: Dream Drop Distance, as these sleeping worlds are entered through diving, a mini-game similar in format to the original Gummi Ship mini-game but with some characteristics from the Kingdom Hearts II iteration, such as bosses that must be defeated before you are able to proceed to the world.

According to Kingdom Hearts Birth by Sleep, the pathways between the worlds are known as the Lanes Between.

There are six known ways to travel through the worlds:
 * Piloting a Gummi Ship; as Gummi Ships are composed of fragments of shattered barriers, they are capable of passing through them.
 * The "Star Shard" that Mickey took from Yen Sid to travel across worlds during Kingdom Hearts Birth by Sleep. The downside to this method of travel is that if the user does not know how to control the shard, the destination and time of activation will be random.
 * Utilizing the Corridors of Darkness; this is a faster means of travel than the Gummi Ships, but those who use them are at great risk of being corrupted or destroyed by the darkness.
 * Teleportation, used by beings that possess powerful magic; Merlin was able to teleport himself, Sora, Donald, and Goofy from Hollow Bastion/Radiant Garden to Disney Castle, as well as teleport Scrooge McDuck to Radiant Garden in Birth By Sleep. Maleficent is also capable of teleportation between worlds.
 * Keyblade Glider; Terra, Aqua, and Ventus can change into their armored form and turn their Keyblades into vehicles that can travel to other worlds by using the Lanes Between.
 * Time travel, such as used by Ansem, Seeker of Darkness, Young Xehanort, Yen Sid and Pete. However, Young Xehanort's method of time travel is trickier than the Yen Sid and Pete's; there needs to be a version of himself where he needs to go and he can only go backwards or forwards in time.

Stars
Stars are massive, luminous balls of plasma that are held together by their own gravity.

In the Kingdom Hearts games, each star is the representation of one specific world. Should a star stop shining, that would mean that particular world has disappeared from existence, most likely from destruction by the Heartless.

In Kingdom Hearts, many stars disappeared. In Mickey's Letter to Donald (before Destiny Islands is attacked by the Heartless), Mickey mentions the fact that the stars have been disappearing, one by one, and so he went to find out why. When Donald and Goofy first arrived at Traverse Town, they discovered a star corresponding Destiny Islands fade out of existence. They were restored after Sora and his friends stopped Ansem's plan to plunge the world into darkness.

In Kingdom Hearts II, Mufasa implies that there are stars to represent certain individuals as well, such as when he told young Simba that all the great kings of the Pride Lands are looking at them in the form of stars. Years later, Simba tries to reach out to his deceased father,and he appears to him immediately. The same implication happens in Kingdom Hearts Birth By Sleep, when Master Yen Sid detects that "Eraqus's star has blinked out", after he is struck down by Master Xehanort.

Realm of Light
The Realm of Light (光の世界, Hikari no Sekai) is a realm made up mostly of light and makes up almost half of the Kingdom Hearts universe, similar to the Realm of Darkness. Like the Realm of Darkness, the Realm of Light has a Keyblade, the Kingdom Key, which chose Sora as its wielder.

Most of the worlds in the Kingdom Hearts universe are found here, save for those in the Realm Between, the Realm of Sleep and the Realm of Darkness. It can be presumed that most of the Worlds accessible by the Gummi Ship are either within the Realm of Light, or are related to it, like Twilight Town.

In Kingdom Hearts II, one notable citation had been made by Sora regarding the Realm of Light during the scene of Sora and Riku at the "end of the road" after defeating Xemnas: ''The other side... The realm of light is safe now. Kairi, the King and the others are there''.

Door to Light
The door leading to the Realm of Light is called the Door to Light. It was the door Sora and Riku went through while they were stuck in the Dark Margin. It is not certain what caused the door to appear, though one reason could be, as Riku pointed out at the end of the game, the light within Sora's heart, which was brought out by Kairi's Letter (prior to reading it, Sora had willingly given up hope of returning home).

Its counterpart is the Door to Darkness.

Realm of Darkness

 * Main article: Realm of Darkness

The Realm of Darkness )闇の世界, Yami no Sekai) is a realm that lies opposite the Realm of Light. There are few people who have lived or are living here, such as Aqua, Ansem the Wise, and Riku, and it is instead inhabited by the Heartless and other dark beings. The only known Keyblade of the Realm of Darkness is the Kingdom Key D, wielded by Mickey. The Kingdom Hearts of Worlds' Hearts began growing in the Realm of Darkness after the Heartless plague was unleashed on the Realm of Light.

Door to Darkness

 * Main article: Door to Darkness

The Door to Darkness is a door in the Realm of Darkness that leads to the deepest, vastest darkness. This darkness can attract an endless swarm of Heartless. Beneath this darkness, however, is the light of Kingdom Hearts. Sora and King Mickey worked together to close the Door to Darkness in the original Kingdom Hearts. Its counterpart is the Door to Light.

Realm Between
The Realm Between is the third realm in the Kingdom Hearts series, and lies on the boundary between the Realms of Light and Darkness.

Few worlds exist within it, and most have some special nature or purpose. As of now, Traverse Town, Land of Departure/Castle Oblivion, Twilight Town, Mysterious Tower, and The World That Never Was are the only worlds confirmed to exist within the Realm Between. Each separate world exists closer to either the Realm of Light or the Realm of Darkness, with the only exception being Twilight Town, which exists exactly in the middle of the two realms.

Lanes Between
The Lanes Between are a series of "roads" between the worlds in Kingdom Hearts Birth by Sleep and Kingdom Hearts 0.2 Birth by Sleep -A fragmentary passage-. Ventus, Aqua, and Terra frequently use these paths to navigate the worlds. The presence of Darkness is very strong within them, forcing travellers to wear their Keyblade Armor as a safety precaution. At the end of Kingdom Hearts 0.2 Birth by Sleep -A fragmentary passage-, Sora uses his Keyblade to open a portal to the Lanes Between. He then directs the Gummi Ship to travel into the portal.

To enter the Lanes, the Keyblade wielder raises his or her Keyblade to the sky, and creates a portal which appears somewhat similar to a Dark Corridor. Having opened the way, the protagonists in Kingdom Hearts Birth by Sleep summon their respective Keyblade Gliders and use them to enter. The Lanes themselves resemble the Corridors of Darkness, but with a color scheme closely resembling the Aurora Borealis.

Realm of Sleep
The Realm of Sleep is comprised of Sleeping Worlds which Sora once saved from the darkness but which did not return to the Realm of Light following Sora's victory over Ansem, Seeker of Darkness. After Sora seals the Door to Darkness with the help of Mickey, many worlds are restored from their demise, but a few are submerged into a deep slumber that prevents them from waking fully until the Keyhole in each world has been unlocked. The reasons for this slumber are unknown. Sora and Riku are sent into the Realm of Sleep by Yen Sid in Kingdom Hearts 3D: Dream Drop Distance in order to release those worlds from their slumber and for the pair to complete their Mark of Mastery exam.

The sleeping worlds found within the Realm of Sleep in Kingdom Hearts 3D: Dream Drop Distance each one carry their own characteristics and unique features which set them apart from the rest. In Country of the Musketeers and Symphony of Sorcery, the dreams therein are of the past, whereas other worlds carry storylines entirely devoid of any relation to previous happenings in the Kingdom Hearts series. Traverse Town also exists within the Realm of Sleep, having been brought into existence for Joshua to have an opportunity to save Neku Sakuraba and his friends from the demise of their home world.

While Heartless and Nobodies reside in both the Realms of Light and Darkness, in the Sleeping Worlds Dream Eaters take their place, taking the form of Spirits and Nightmares.

Worlds
The World (世界, Sekai) is a location that appears in all of the series. Serving as the "levels" for the games, Sora and other characters are charged with visiting and protecting them through the course of the series. By defending the worlds from the Heartless, Nobodies, or other enemies, the series' respective protagonists keep the Darkness from spreading and the worlds from being manipulated or destroyed.

At the end of every world (in the original Kingdom Hearts) Sora, Donald, and Goofy have to fight a boss of that world (which is either a giant Heartless, or a villain) which opens the Keyhole area when defeated. At the end Sora locks the Keyhole and earns a Gummi that will let him go to the next world.

Each world that appears in the Kingdom Hearts series has its own distinct look, and for the most part hold true to the franchise they are based on. Often the plot of the game in that world will be based on its original source.

Almost all worlds can be visited in the course of the game and are part of the playthrough; there are exceptions, though, since some places can be seen in cinematics but not actually accessed by Sora's party. All worlds are separate from one another, and with a few exceptions, most people are unaware of the existence of other worlds.

World Characteristics
There are more than over many dimensional worlds that have appeared in the Kingdom Hearts series so far. Most of them are based on various animated features and contain locations and characters from or inspired by the franchises. As a result, worlds are greatly varied in appearance, style, and nature, as their sources range from the oldest to more current canon.

In addition to the Based-on worlds, twelve worlds are exclusives that were created by game developers Square Enix just for the Kingdom Hearts series. They are not part of the Disney film canon, nor Square Enix's games canon, but do tend to be populated with Square Enix characters, especially from the Final Fantasy series, as well as the occasional Disney character or original characters created just for Kingdom Hearts.

Some worlds have names that don't seem to accurately reflect what is found there. A famous example is Neverland in Kingdom Hearts; Sora and company get to go through Captain Hook's ship and fly around the Clock Tower, but never actually reach the island Neverland where Peter Pan and Tinker Bell live. To further confuse things, some worlds in Kingdom Hearts II contain what could almost be considered sub-levels or second worlds within them, such as the Underworld at Olympus Coliseum or Christmas Town in Halloween Town.

List of Main universes

 * The Game & Watch universe (1980)
 * The Pac-Man universe (May 22, 1980)
 * The Mario universe (July 14, 1983)
 * The Donkey Kong universe (July 9, 1981)
 * The Wrecking Crew universe (June 18, 1985)
 * The Wario universe (January 21, 1994)
 * The Yoshi universe (August 1995)
 * The Ice Climber universe (January 30, 1984)
 * The Punch-Out!! universe (February 1984)
 * The R.O.B. universe (July 26, 1985)
 * The Legend of Zelda universe (February 21, 1986)
 * The Fantasy Zone universe (March 28, 1986)
 * The Metroid universe (August 6, 1986)
 * The Outrun universe (September 20, 1986)
 * The Alex Kidd universe (November 1, 1986)
 * The Kid Icarus universe (December 19, 1986)
 * The Thunder Blade universe (1987)
 * The After Burner universe (July, 1987)
 * The Metal Gear universe (July 7, 1987)
 * The Street Fighter universe (August 30, 1987)
 * The Shinobi universe (November 1987)
 * The MegaMan universe (December 17, 1987)
 * The Final Fantasy universe (December 18, 1987)
 * The Power Drift universe (1988)
 * The Maze Hunter universe (1988)
 * The Galaxy Force universe (May 1988)
 * The Altered Beast universe (August 1988)
 * The EarthBound universe (1989)
 * The Golden Axe universe (June 1989)
 * The Fire Emblem universe (April 20, 1990)
 * The Bonanza Brothers universe (June 18, 1990)
 * The F-Zero universe (November 21, 1990)
 * The Sonic the Hedgehog universe (June 23, 1991)
 * The Puyo Puyo universe (October 25, 1991)
 * The Kirby universe (April 27, 1992)
 * The Ecco the Dolphin universe (July 31, 1992)
 * The Star Fox universe (February 21, 1993)
 * The Virtua Fighter universe (October 1993)
 * The Virtua Striker universe (1994)
 * The Panzer Dragoon universe (1994)
 * The Pokémon universe (1996)
 * The NiGHTS universe (July 5, 1996)
 * The House of the Dead universe (September 13, 1996)
 * The Crazy Taxi universe (1999)
 * The ChuChu Rocket! universe (November 11, 1999)
 * The Samba De Amigo universe (December 1999)
 * The Space Channel 5 universe (December 16, 1999)
 * The Shenmue universe (December 29, 1999)
 * The Jet Set Radio universe (June 29, 2000)
 * The Skies of Arcadia universe (October 5, 2000)
 * The Animal Crossing universe (April 14, 2001)
 * The Total War universe (June 13, 2001)
 * The Super Monkey Ball universe (June 23, 2001)
 * The Pikmin universe (December 2, 2001)
 * The Sly Cooper universe (September 23, 2002)
 * The Billy Hatcher and the Giant Egg universe (September 23, 2003)
 * The Football Manager universe (November 5, 2004)
 * The Company of Heroes universe (September 12, 2006)
 * The Wii Fit universe (December 1, 2007)
 * The Bayonetta universe (October 29, 2009)
 * The Kingdom Hearts universe

Past
According to the story told by Kairi's Grandma in the Hollow Bastion's Library, long ago, there was one single world that was constantly bathed in the warmth of Light. When people began to fight over the Light within their world, Darkness appeared in their hearts, and the world was consumed. However, fragments of light remained within the hearts of children. From this light, children were able to rebuild the lost world.

However, darkness still existed, which caused the worlds to be separate from each other, divided, waiting for the true light to return. This was explained in more detail in Birth by Sleep, where it was revealed the fight was between the many Keyblade holders over Kingdom Hearts, and eventually led to the Keyblade War.

Prior to Kingdom Hearts, the worlds were surrounded by barriers, to prevent outside interference, making it impossible for different worlds to have contact. The arrival of the Heartless caused the barriers between the worlds to crumble and disappear, and some worlds were even consumed by the Heartless. Gummi Blocks are actually pieces of these broken barriers.

Those who travel between worlds are advised to avoid meddling in the affairs of other worlds, and informing their inhabitants of the existence of other worlds, in order to maintain a balance of separation. To this end, several characters, notably Sora, Donald Duck, and Goofy, magically alter their physical appearances in certain worlds to avoid standing out. For example, they become sea creatures in Atlantica, Halloween monsters in Halloween Town, jungle animals in Pride Lands, and computer A.I.s in Space Paranoids.