Kingdom Hearts The first titular game was released in 2002 to massive approval and widespread acclaim . " Kingdom Hearts " was followed by a sequel , ' , released in 2004 , which connected to ' , released a year later . Since the release of " Kingdom Hearts II " , four more games in the series have been released : ' for the Nintendo DS , acting as a prequel to " Kingdom Hearts II " , ' for the PlayStation Portable , acting as a prequel for the entire series , ' for mobile phones ( and later the Nintendo DS ) , acting as a " bridge game " to the latest installment ' on the Nintendo 3DS system . It will lead into the recently announced at E3 2013 " Kingdom Hearts III " . Much like the International versions of " Final Fantasy " games , the series also has updated versions of " Kingdom Hearts " and " Kingdom Hearts II " known as " Kingdom Hearts Final Mix " and " Kingdom Hearts II Final Mix " . In Japan , " Kingdom Hearts II Final Mix + " was a two - pack collection that consisted of " Kingdom Hearts II Final Mix " and a PS2 remake version of " Kingdom Hearts : Chain of Memories " known as " Kingdom Hearts Re : Chain of Memories " ; the latter was later released as a standalone title outside of Japan . The " Final Mix " versions of " Kingdom Hearts " , " Kingdom Hearts II " , and " Birth by Sleep " were released outside Japan for the first time in " Kingdom Hearts HD 1 . 5 Remix " , and " Kingdom Hearts HD 2 . 5 Remix " for PlayStation 3 . Gameplay . The series contains elements of both action and role - playing games . The games are driven by a linear progression to the next story event , usually told in the form of a cut scene , though there are numerous side quests available that provide bonus benefits to the characters . The player is primarily in control of the principal protagonist of the series , , who is usually accompanied by and as NPC supports whose behavior can be altered to fit the player ' s needs by preset commands that determine how they act in different situations . The games feature real - time combat that incorporate physical attacks , magic , and summonings . " Kingdom Hearts II " introduced the " Reaction Command " feature , wherein hitting the Triangle button in response to an on - screen prompt at the right time provokes a special reaction , usually a special cinematic attack unique to the enemy being fought . Gummi Ships are another common theme in the series , though they are only featured in the first and third installment . The Gummi Ships serve as the main mode of transportation between worlds in the games . The gameplay for the Gummi Ships sections is more akin to a rail shooter , where players shoot enemies as they fly along a preset course , earning new Gummi parts as they defeat enemies and completing the course to unlock the next worlds . The games also feature a journal which is accessible from the main menu , keeping track of information regarding the story , characters , enemies , and locations . In games where Sora is the lead character , the journal is kept by Jiminy Cricket , who was appointed by Queen Minnie as the royal chronicler . The games are influenced by their parent franchise , " Final Fantasy " , and carry its gameplay elements over into their own action - based , hack - and - slash system . Like many traditional role - playing games , " Kingdom Hearts " features an experience point system which determines character development . As enemies are defeated , the player gains experience which culminate in a " level - up " , where the characters grow stronger and gain access to new abilities . The amount of experience is shared with all party members and each character grows stronger as experience is gained . Story . The " Kingdom Hearts " series focuses on the adventures of and his friends , and . The three live on a small world called Destiny Islands , and dream of exploring other places . One night , beings of darkness called attack the island , and Sora receives a special sword called a to fight them off . The island is destroyed and Sora awakens in Traverse Town , where he meets with Goofy and Donald Duck , and joins with them to find their ruler , King Mickey , and Riku and Kairi . Sora travels various worlds fighting the Heartless , and learns that the Disney villains have recruited Riku to their cause , to gather the Seven Princesses of Heart , of which Kairi is one . However , the Disney villains are being manipulated by a man named , a researcher who was studying the Heartless . Ansem wishes to use the Princesses to open passage to the Heart of all worlds , Kingdom Hearts , and claim its power . Sora and his allies defeat Ansem , but in the process Mickey and Riku are trapped in the Realm of Darkness . In " Kingdom Hearts : Chain of Memories " , Sora is confronted by a man in a black coat and led to Castle Oblivion , a fortress on the borders of the realms . Members of a mysterious group , Organization XIII , are holding a girl named hostage , and use her to erase Sora ' s memories and replace them with new ones befitting their plans . Sora defeats the Organization members , but must be put to sleep to repair the damage to his memories . Meanwhile , Riku awakens in the basement of the castle , and with Mickey ' s help fights his way out . A year later in " Kingdom Hearts II " , Sora awakens and pursues the remaining members of Organization XIII . , Mickey ' s mentor , explains that the Organization is made up of Nobodies , the empty shells formed by bodies of beings that lose their hearts to darkness . Their leader , , is the Nobody of a man named , and the " Ansem " Sora defeated as Xehanort ' s Heartless ; the real Ansem has been in hiding under the alias DiZ after Xehanort betrayed him . Sora reunites with Riku , Kairi , and Mickey , and the group destroys the Organization and Xemnas . The next two chronological games in the series , " Kingdom Hearts 358 / 2 Days " and " Kingdom Hearts coded " , follow a series of side - stories to the main plot . In " 358 / 2 Days " , the player takes control of Roxas , Sora ' s Nobody that was born when Sora lost his heart in the first game . While Sora sleeps after " Chain of Memories " , Roxas joins Organization XIII and becomes close friends with a girl named , who is revealed to be an incomplete clone of Sora . Roxas is forced to destroy her to stop Xemnas ' plans to use both of them , and is then captured by Riku to aid in restoring Sora ' s memories . In " coded " , a mysterious message appears in Jiminy ' s Journal , and Mickey creates a digital recreation of the journal to find the source with help from a digital recreation of Sora . The source is revealed to be information that Ansem planted in Sora ' s heart during his recovery that concerns three lost Keyblade users . " Kingdom Hearts : Birth by Sleep " takes place ten years before the first " Kingdom Hearts " , and follows the Keyblade users Terra , Aqua , and Ventus . A Keyblade Master , Master Xehanort , has gone missing , and monsters called Unversed are attacking the worlds , led by , Master Xehanort ' s former apprentice . It is revealed that Master Xehanort wishes to cause a Keyblade War as part of a plan to take the power of Kingdom Hearts . To ensure he will be strong enough to see his plans to fruition , he takes control of Terra ' s body , creating a younger Xehanort . Terra ' s spirit reforms in his armor and defeats Xehanort , and Xehanort is later felled in battle with Aqua , losing his memories and coming into Ansem ' s care . In the outcome of the battle , Vanitas is destroyed , Ven ' s heart is shattered and his body placed in Castle Oblivion to recover , and Aqua is trapped in the Realm of Darkness . In " Kingdom Hearts : Dream Drop Distance " , Yen Sid and Mickey contact Sora and Riku to give them a trial to become Keyblade Masters so they may rescue the three warriors . Their trial is attacked by a young Master Xehanort , traveled through time as part of a scheme set in place by his older self to gather his various incarnations from across time . It is also revealed that with the destruction of Ansem and Xemnas , Master Xehanort ' s heart and body have reformed to revive him . Sora and Riku are able to stop Master Xehanort ' s plan and his other incarnations vanish back to their original time periods , but Master Xehanort escapes to continue his plans to seize Kingdom Hearts . Riku passes his trial and is named a Keyblade Master , and brings Kairi to Yen Sid to train with the Keyblade . Finally , there is " Kingdom Hearts χ " , a sidegame taking place many years even before " Birth by Sleep " , and follows the adventures of Keyblade users in service to five Keyblade apprentices . Characters . " Final Fantasy " characters . The majority of the " Final Fantasy " characters in the series act as " neutral " characters and appear in the worlds that are not based on Disney worlds , specifically Destiny Islands , Traverse Town , Twilight Town and Hollow Bastion / Radiant Garden . The exception is Olympus Coliseum , where a handful of " Final Fantasy " characters pass through . So far , twenty - four characters from the " Final Fantasy " series have appeared in the " Kingdom Hearts " games . The series implies that Radiant Garden is the " Final Fantasy world " within the series , as Leon , Aerith , and Yuffie claim it was their home until it was taken over , and in " Kingdom Hearts II " , Cid , Cloud , Tifa , and Sephiroth also appear there . In " Kingdom Hearts " , the cast of " Final Fantasy " characters was much smaller , with only nine of them playing a major role . This count was increased dramatically in " Kingdom Hearts II " to over a dozen , and their importance to the storyline also increased . In both games , several of the characters appear in Olympus Coliseum as opponents . Connections to the " Final Fantasy " series . Besides the numerous characters from the " Final Fantasy " series that appear , several other aspects of the series directly influence the gameplay of " Kingdom Hearts " . The series uses the same naming patterns as " Final Fantasy " for its spells and items , items and spells such as Hi - Potion s , Tent s , Fire and Stop appearing , among many others . The series also universally uses the same spell suffix systems as " Final Fantasy " , " - ra " denoting tier two spells and " - ga " denoting tier three . There are Summon spells that can call allies into battle , using mechanics similar to the summon sequences of " Final Fantasy X " . Although the summons are all Disney characters ( except for a Cloud summon in " Chain of Memories " ) , a Bahamut summon was meant to be in the original game , but was later removed as the development team decided that all the summons in the game were to be of iconic Disney characters instead . Several weapons are named after " Final Fantasy " weapons , including the Ultima Weapon , Fenrir , and Save the Queen . The various Gummi ships used to travel between worlds are named after " Final Fantasy " ships and concepts , and include " Highwind " , " Fal con " , and " Invincible " . Ability Points are used to assign various special attacks and support powers to party members . In " Kingdom Hearts II " , Limit Breaks appear as techniques that allow Sora and an ally to unleash a series of powerful attacks at the cost of all Sora ' s MP . Some of these Limit Breaks , like Bushido and Comet , again take their name from " Final Fantasy " games . In " Birth by Sleep " the player is able to fuse commands together to create stronger ones and can infuse items in the fusion to attach abilities to the new command , identical to Materia Fusion in " Crisis Core " . The Nobody enemy types are based on recurring " Final Fantasy " jobs and show some similar behavior — Dragoon Nobodies fight with lances and use Jump attacks , and Gamblers battle using dice and cards . The Organization members themselves also roughly fit such profiles — for example , Zexion can mimic the attacks of enemies similar to a Blue Mage . Each member also controls one element , such as Water , Light , and Earth . Besides Nobodies , several Heartless are named for " Final Fantasy " enemies , such as the Behemoth and Darkside . Several enemies also masquerade as pots or jars until attacked , or hide in treasure chests and attack when they are opened , a reference to mimics and Monster - in - a - box . When fighting in Olympus Coliseum , Sora uses victory poses based on Squall and Cloud ' s , while Roxas uses Squall ' s victory pose in " 358 / 2 Days " . Riku ' s growth through the series parallels Kain Highwind , and to a lesser degree Cecil Harvey . Similar to the two , Riku began the series as an antagonist using the powers of darkness and was manipulated by Xehanort , but reformed and become a heroic character that joined Sora on his adventures , now using the powers of darkness to fight for light . Riku ' s signature weapon , Soul Eater , is named after Cecil ' s ability as a Dark Knight , and similar to Kain and Cecil ' s love triangle with Rosa , it is strongly hinted Sora and Riku have romantic feelings for their mutual friend Kairi , with Sora being the victor in the competition . The " Kingdom Hearts " series in turn has retroactively influenced the " Final Fantasy " series . " Kingdom Hearts " was the first game to feature Sephiroth with a single black wing behind his right shoulder , an element of his appearance that was later included in the " Compilation of Final Fantasy VII " . Gameplay elements of " Dissidia Final Fantasy " are influenced by " Kingdom Hearts " , such as chaining attacks in different ways based on the timing of button presses . Quickmove and Chase Sequence s are similar to Reaction Commands in " Kingdom Hearts II " , and EX Mode is similar to Sora ' s Drive Forms in the same game , granting an enhanced set of abilities and an altered appearance for a short time while Sora ' s Drive Gauge depletes over time , reverting form when it empties . Sora makes his first appearance in a " Final Fantasy " game with a guest appearance in " World of Final Fantasy " . He is a free DLC character as a Summonable Champion during battle .