Mickey Mouse

Mickey Mouse, formally referred to as The King, Your Majesty, or King Mickey, is the king of Disney Castle and a recurring character in the Kingdom Hearts series. Originally a ship's hand working with Captain Pete at Timeless River, Mickey became a student of the Keyblade Master Yen Sid. After completing his training and becoming a Keyblade Master himself, Mickey travels to other worlds to battle the forces of darkness. Although he is the chosen Keyblade wielder for the Realm of Darkness, he follows the path of light. Once believing that darkness had to be eliminated, he eventually realized that light and darkness are interdependent and cannot exist without the other due to his encounters with Riku, who he forms a strong bond with over the course of the series.

Mickey was a main player in the conflict with Master Xehanort, and was later one of the first to notice the threat of the Heartless, inventing the first Gummi Ship to travel to other worlds in order to fight against the monsters.

Kingdom Hearts χ
King Mickey's power was channeled by the Book of Prophecies to form various s, specifically, , , , , , and.

While using the Star Shard to search for Donald and Goofy, Mickey, Chip, and Dale are unknowingly brought to to the past by unknown means, and land in Daybreak Town's Market just in time to save the Player from a swarm of Wizards. They introduce themselves and learn that the Player is trying to help Donald and Goofy rebuild their Gummi Ship in order to return home, so the King sends Chip and Dale to help finish the ship. As Mickey ponders the events, he notices Foreteller Invi watching him from a nearby rooftop and speculates that a force other than his Star Shard led him there.

After the Player retrieves the last of the needed Gummi Blocks and the ship is finished, Mickey thanks them for their help before departing.

Between Kingdom Hearts χ and Kingdom Hearts Birth by Sleep
When he was young, Mickey worked as a deck hand with his captain, Pete. He and Pete sailed the steamboat Willie throughout Timeless River. This past association causes Pete to refer to Mickey as "the Boat-Boy King."

When Sora comes from the future using a door in the Hall of the Cornerstone, he, along with the future versions of Donald Duck and Goofy, mistake Mickey for being himself from the future. Four times, Mickey appears at scenes of trouble, either in peril (or appearing to be so), saving the day, or both. On one such occasion, his house is attacked by hordes of Heartless and a mini black hole that sucks up all his furniture. After each time Sora helps him out, Mickey shakes his hand and leads him to another scene of peril.

At some point, Mickey gains knowledge of the Keyblade and begins to study them, as well as how to travel to other worlds. Eventually, he travels to Country of the Musketeers to solve a problem, along with Donald and Goofy. Though his skills with a sword are not excellent, he nevertheless doesn't give up on his duty and continues to fight for everything that defines a Musketeer. His task while here is to protect Minnie, who would eventually join him in ruling over Disney Castle.

At a later point in time, he finds his way to the Mysterious Tower, where Master Yen Sid takes him in as an apprentice. One day, Master Yen Sid leaves his sorcerer's hat out and Mickey places it on his head, casting spells of all types. By enchanting the brooms, he has them do his chores and eventually decides to take a nap, only to awaken and find that the spell has gone horribly wrong and chaos is running rampant, with the entire tower flooded.

Despite his mistakes, Yen Sid keeps him on as his apprentice and Mickey eventually is able to wield the Star Seeker Keyblade.

Kingdom Hearts Birth by Sleep
While Terra, Ventus, and Aqua search for Master Xehanort and Vanitas, King Mickey undergoes the Mark of Mastery Exam under the supervision of Yen Sid at the Mysterious Tower, accompanied by Donald and Goofy, during which he uses the Star Seeker Keyblade. Later on, Mickey runs away without Yen Sid´s permission, using a Star Shard that allows him to travel throughout other worlds; however, it works rather randomly, as he has not learned how to control it. Terra witnesses the King's leave when he first visits the tower.

Upon visiting the Mysterious Tower, Terra watches Mickey's Star Shard take him to the Keyblade Graveyard. The Star Shard knew that Mickey needed to be there to save Ventus. When Ventus loses a fight with Vanitas, he steps in to help. They successfully drive him off before Mickey's Star Shard brings them to Radiant Garden. He later teams up with Aqua (after Ven attempts to get inside the Radiant Garden castle), rescuing a young Kairi from the Unverseds' attempt to capture her. He is whisked off to Neverland when the battle ends, telling Aqua to not worry about him.

While exploring Neverland, Mickey is ambushed by Vanitas and knocked unconscious, who then proceeds to kidnap Mickey and take him to the Keyblade Graveyard. Ven tries to help Mickey when he finds out about it, only for them to both get sucked into a vortex. Mickey is left stranded in space before Aqua finds him and takes him back to the Mysterious Tower.

Upon regaining consciousness, Mickey returns to the Keyblade Graveyard, where he helps Aqua battle Ventus, who is possessed by Vanitas, and eventually guides them to the Mysterious Tower, where they discover that Ventus's heart has left his body. Later, after Aqua leaves with Ventus to find him a safe place, Mickey sorrowfully hands in the Star Shard and his Star Seeker Keyblade, thinking he has failed to reach his goal and disappointed his master, and begins to leave. Before he departs, however, Master Yen Sid hands him back the Keyblade with a smile, showing him that he is indeed worthy of the title of Keyblade Master. Mickey then happily accepts it.

Between Kingdom Hearts Birth by Sleep and Kingdom Hearts
After the barriers between the worlds shatter, causing meteors to fall from the sky, Mickey realizes the threat that the Darkness presents. Mickey seeks help for his concerns and the danger he expects. By using the material from the meteors themselves to make a Gummi Ship, Mickey travels to Radiant Garden and meets Ansem the Wise. Mickey befriends Ansem and tells him of his concern about the growing Darkness between the worlds. It is also here that Mickey meets Xehanort, who seemingly disturbs the King. Because of his feelings towards the man and his persistent interest in certain experiments, coupled with the growing threat of Darkness, Mickey advises Ansem the Wise to review the research in his lab's computer.

Sometime during these years, Scrooge and Mickey traveled together to create a transit system.

Kingdom Hearts
Detecting the encroaching darkness, King Mickey left his home, Disney Castle, to search for the Realm of Darkness and its Keyblade in order to seal the Door to Darkness. He left a note instructing his friends, Donald and Goofy, to "find the Key", and arrived in Traverse Town at the same time as Sora. Keeping himself out of sight, he located a Corridor of Darkness leading into the dark realm, and passed through it followed by his dog, Pluto.

Once there, he stumbles upon Aqua, floating unconscious in the void. After a brief reunion, they are attacked by a swarm of Heartless, but manage to defeat them. Mickey is surprised that he has finally found Aqua, and she explains how her sacrifice to save Terra-Xehanort from sinking into darkness trapped her there. Afterward, she joins him on his journey through the Realm of Darkness to find the Keyblade. Eventually, the pair arrive at the wreckage of Destiny Islands and are intercepted by a massive swarm of Heartless at the entrance to the Secret Place. After defeating the Heartless, they enter the cave and discover the Keyblade, but just as Mickey acquires it, they spot Riku, whose body had been stolen by Ansem, Seeker of Darkness, being chased by a swarm of Heartless. Aqua uses her Master's Defender to ensnare the Heartless, allowing Mickey and Riku to escape, but leaving her once more all alone.

Shortly after Ansem is defeated, Mickey and Riku arrive at the Door to Darkness, and help Sora to seal the door to prevent the Heartless from escaping through it. Although Sora is reluctant to leave Mickey and Riku trapped within the Realm of Darkness, Mickey assures them that there will always be the Door to Light, and thanks Donald and Goofy for their loyalty.

Kingdom Hearts: Chain of Memories
Although Sora, Donald and Goofy initially enter Castle Oblivion believing the King to be there, Mickey is only able to send a bit of his light to help Riku in the twelfth basement, when he is attacked by Ansem. When Riku enters the eleventh basement, Mickey is able to project an image of himself, and he makes Riku promise to keep fighting the darkness, while promising to find a way to where Riku is. Riku is then able to call upon Mickey's power in battle as he ascends through the castle's basements.

When Ansem attempts to possess Riku after his fight with Lexaeus in the B4F Exit Hall, Mickey sends his light to drive him off. After Riku emerges from the third basement, Ansem takes advantage of Riku's acceptance of his own darkness to attempt possessing him once again. Mickey's light drives Ansem off once more, and Mickey arrives in person, explaining to Riku that a World Card, leading to Twilight Town, had appeared before him and showed him a path from the Realm of Darkness to where Riku was. Mickey meets Riku at the B2F Exit Hall, happy to see Riku chose not to be put to sleep by Naminé, and they speak with DiZ, who seems familiar to Mickey.

Mickey accompanies Riku to the entrance to the first basement, where Riku intends to face Ansem once and for all. Riku asks Mickey to let him face Ansem alone, and he tries to get Mickey to promise to destroy him if Ansem possesses him again. Mickey refuses and promises instead to rescue Riku, no matter what. After Ansem is defeated, Mickey rescues Riku from the sudden rush of darkness and takes him to the castle's entrance hall. He calms Riku's concerns about the remnants of darkness in his heart by pointing out that Riku's darkness is his own to control, explaining that although he used to think darkness was only bad, he is fascinated by Riku's ability to use light and darkness together and wants to accompany Riku along his chosen path. When Riku thanks "[his] Majesty", Mickey laughs and says that, as a friend, Riku can just call him "Mickey".

Mickey and Riku leave the castle, wearing the black coats given to them by DiZ, who they encounter at the crossroads. He asks Riku whether he has chosen to follow the roads of light or darkness. Riku instead chooses the "road to dawn", and he and Mickey continue on.

Some time after this, the two of them walk through The Great Maw, where Riku momentarily collapses under the strain of the darkness in his heart. Although a concerned Mickey tries to help, Riku shrugs him off. The two of them eventually split up after Riku realized that he couldn't completely rid himself of the darkness festering in him.

Kingdom Hearts 358/2 Days
King Mickey reunites with Riku in the Twilight Town woods, who has taken on the form of Ansem, Seeker of Darkness. Initially perceiving him as an enemy, Mickey readies his Keyblade to attack until Riku calmly ties his blindfold into place, shocking Mickey as he recognizes Riku's changed appearance. After Riku assures Mickey that he has some control over the darkness, he informs him that the Organization is interfering with Naminé's progress to restore Sora's memories. Mickey urges Riku to let him help, but the latter declines. Revealing his plans to face a member of the Organization soon and his insecurity about surviving the fight, Riku makes Mickey promise to guide and protect Sora and their friends once they awaken.

Kingdom Hearts II
Sometime after Riku leaves DiZ's employ, he encounters Mickey and gives him the Munny Pouch that he had stolen from Roxas in the Simulated Twilight Town. Not wanting Sora and Kairi to know about his condition, Riku pleads with Mickey not to reveal his whereabouts or his condition to Sora, and Mickey reluctantly agrees.

Mickey later arrives to help Sora fend off the Nobodies that attacked them in Twilight Town posing as somewhat of a fake Organization XIII member. After the battle, he hands Sora the pouch of munny Riku gave him and instructs him to visit his mentor, Yen Sid, running off afterward. Yen Sid reveals that Mickey's reasons for leaving Disney Castle in the first place was to investigate the mysterious outbreak of Heartless and the more mysterious Organization.

At Hollow Bastion, Mickey reveals the truth about "Ansem", but is reluctant to reveal any information on Riku. He then aides the group in fending off the Heartless that Maleficent has summoned to destroy Radiant Garden. Initially, he orders Sora, Donald, and Goofy to leave Hollow Bastion and leave the Heartless to them, but Donald and Goofy go against his orders when they realize how desperate Sora is to help Leon. He later confronts them after they defeat Demyx, at first appearing angry, but soon simply decides to allow them to help.

When Goofy apparently dies after taking a nasty blow to the head while saving Mickey from the same fate, Mickey swears that the Heartless would pay and permanently discards his Organization XIII disguise. They are later relieved to discover that Goofy was only unconscious. When he and Sora confront Xemnas, he jumps after Xemnas into a corridor of darkness before it closed, thus preventing Sora, Donald and Goofy from going after him, but since he appears later in Twilight Town, it is apparent that he could not follow Xemnas all the way back to the Organization's base.

Sora and the others meet him in Twilight Town, where they find a way into The World That Never Was through the Simulated Twilight Town DiZ had created. When they enter the world, Mickey goes ahead of Sora to look for Ansem the Wise. He eventually finds him, and rescues him from a group of Nobodies. Ansem then attempts to use his machine to convert Kingdom Hearts into data, but was unsuccessful and vanishes when the machine explodes.

Mickey then confronts Xemnas with Sora, Riku, Kairi, Donald and Goofy, and watches as Xemnas opens Kingdom Hearts. Xemnas then blocks out King Mickey and Kairi from participating in the final fight, first by launching a building at him and Kairi, closing the door to Kingdom Hearts, and later closing the dark portal to the Destiny Islands, preventing Mickey, Kairi, Donald, and Goofy from returning to aid Sora and Riku.

After Sora and Riku end the Organization's plot, Mickey waits with Donald, Goofy, and Kairi on Destiny Islands for their return. Once they do, he runs to Riku and congratulates them both for defeating Organization XIII. During the end credits, King Mickey is seen returning with Donald, Goofy, Scrooge McDuck, Huey, Dewey, and Louie, Pluto, and Jiminy to Disney Castle, where he shares a kiss with his wife Queen Minnie.

Soon after, Mickey sends Sora, Riku, and Kairi a bottled letter.

Kingdom Hearts coded
Mickey digitizes Jiminy's Journal to investigate a mysterious message saying: "We must return to free them from their torment". When bugs appear in the digital system, he decides to create a data version of Sora to fix them.

Following the digital Sora's time in Traverse Town, he is attacked by Heartless. After disposing of them with the Star Seeker, he tries to leave the library to check the castle, but finds himself locked in, along with Jiminy, Donald, and Goofy. Somehow, they have been transported into the digital journal itself. While in the journal, he joins forces with Data-Sora and the journal itself (in the form of Riku) to dispatch the Heartless and debug the digital world. After defeating Sora's own Heartless, who was corrupting the journal, Mickey and his friends are returned to the real world when the debugging is completed, but a message claiming that a door to a new world has opened appears on the screen. Preparing for another adventure, Mickey requests to be taken into the digital world again to solve this new mystery.

Inside, he escorts Data-Sora throughout Castle Oblivion until they encounter the data version of Naminé, who tells them about Terra, Ventus, Aqua, and the reason behind the Bug Block corruption, which was caused by the real Naminé when she removed Sora's memories and later restored them.

After everything in the journal was restored, Mickey returns to the real world to write the letter to Sora to tell him about those who need him to heal their sadness, and a new journey is about to begin.

Later, Mickey reports to Yen Sid that he believes he has finally found where Ventus's missing heart is, leaving only Terra's heart to be found. Their discussion quickly shifts towards the topic of Master Xehanort, who Mickey is stunned to learn will return due to the defeat of his Heartless, Ansem, and his Nobody, Xemnas, and the subsequent restoration of Xehanort. Fearing that they may have to fight more than a "single one of Xehanort", Yen Sid orders Mickey to bring Sora and Riku before him so that they may take the Mark of Mastery exam.

Kingdom Hearts 3D: Dream Drop Distance
Mickey is present with Donald and Goofy in the Mysterious Tower as Yen Sid puts Sora and Riku through the Mark of Mastery exam in the Sleeping Worlds. While overseeing it, Mickey receives a note from Maleficent and Pete along with Minnie's crown, ordering him to return to Disney Castle, where he finds them holding Minnie hostage. Maleficent demands that Mickey hand the Datascape over to her, but Mickey refuses. Lea arrives and helps free Minnie. Mickey orders Maleficent to leave, and he and his friends return to the Mysterious Tower.

Later on, when Sora and Riku do not return from the Sleeping Worlds at the expected time, Mickey enters and finds Riku in Where Nothing Gathers, using a Stopza spell to freeze Young Xehanort and help him save the comatose Sora, but Xehanort remains unaffected by the spell and knocks Mickey aside in order to battle Riku. Following the fight, Mickey and Riku meet the revived Master Xehanort, who explains to them the details of his past endeavors and his continuing plans to recreate the χ-blade and restart the Keyblade War. Mickey openly accuses Master Xehanort of ruining the lives of Terra, Aqua, Ven and Master Eraqus, but Xehanort merely quips that it was their destiny. As Master Xehanort prepares to turn Sora into a vessel for a piece of his heart, Xemnas physically restrains Mickey from rescuing him. Lea arrives in time to protect Sora, and Ansem responds by releasing his Guardian, who grabs Mickey and Riku, but is knocked out by Donald and Goofy. Master Xehanort and the rest of Organization XIII are forced to retreat, but swear revenge.

Mickey helps bring Sora's body back to the tower, where Riku manages to mend his broken heart and awaken him. Riku is named a Keyblade Master for this and Mickey congratulates his friend, but is shocked when Lea summons his own Keyblade. Later on, Yen Sid tells Mickey of their plans to form a group of seven Keyblade warriors of Light to counter Master Xehanort, and Mickey is visibly stunned when Yen Sid's newest student turns out to be Kairi.

Along their journey, Sora and Riku also cross paths with two past incarnations of Mickey: one as a Musketeer and the other as a Sorcerer apprentice under Yen Sid.

Kingdom Hearts 0.2 Birth By Sleep -A fragmentary passage-
Shortly after Kairi's arrival, Mickey tells her and Riku the story of how he found Aqua in the Realm of Darkness and what happened to her when he and Riku helped Sora seal the Door to Darkness. After explaining, he thinks he hears Aqua's voice in the distance. A frustrated Riku demands to know why Mickey didn't tell him sooner, but Mickey clarifies that he had to respect her choice, his claims bolstered by Yen Sid's insistence that had Riku found out sooner, he and Sora would have staged a fruitless rescue mission. When Yen Sid orders Kairi to train with Lea under Merlin, Mickey explains to Kairi who Lea is. Yen Sid then assigns Riku and Mickey the mission to rescue Aqua and gives the two Keyblade Masters new clothes from the three fairies to shield them from the darkness.

Kingdom Hearts Re:coded
King Mickey's KH CoM outfit is available through the King Mickey A ensemble, and his KH II outfit is available through the King Mickey B ensemble. An Avatar named "ClubLeader", based on his KH I outfit, can send a Balloon Letter in the Avatar Sector via Tag Mode.

Kingdom Hearts Unchained χ
King Mickey's KH CoM outfit is available through the and  Avatar Boards, and his KH II outfit is available through the, and  Event Boards.

Kingdom Hearts III
Mickey will journey along with Sora, Donald, and Goofy in Kingdom Hearts III.

Disney Infinity 3.0
Mickey Mouse's Kingdom Hearts attire can be worn by Mickey in the toys-to-life game  as an exclusive giveaway from Disney's D23 Expo 2015.

Appearance
Mickey is an anthropomorphic mouse with black fur, round ears of the same color, and a thin, long, black tail. The fur on his face is cream-colored. His usual outfit in the Kingdom Hearts series is a modified version of the one he wears in modern Disney cartoons. He wears a short-sleeved jacket with white lining. The top half of this jacket is black, while the bottom half is red, and there are two yellow straps dangling in front of it. His pants are red and sport a zipper going down the front of each leg. Each leg also has a yellow pouch with a black strap that partially cover the zipper, as well as a blue strap on the outer side of each pant leg. Mickey wears very large, yellow shoes with grey backs and two orange, intersecting straps attached to the front of each shoe. Throughout the Kingdom Hearts series, Mickey appears in numerous outfits and forms from different worlds. In all of his appearances, except for when he wears the black coat, Mickey dons the famous, white gloves common to most older Disney characters.

Personality
In the past, Mickey is a mischievous and playful individual, often skipping work and getting himself into trouble. He tends to steer clear of dangerous fights, but he shows moments of bravery, such as when he saves Sora from a Heartless ambush. Even as an apprentice under Yen Sid, he often goes against his master's instructions, whether it is to get out of doing chores or to explore other worlds.

As king of Disney Castle, Mickey is much more responsible and dutiful. He commands the respect and loyalty of his subjects, especially Donald and Goofy. Mickey is very friendly and loyal, always thinking positively. He is always ready to help his friends and tries to protect them at any costs. He always tries to keep the promises he makes to his friends. When he sees his friends get hurt, he becomes surprisingly serious and angry, such as when Goofy appears to be mortally wounded after saving him during the Battle of the 1000 Heartless.

Mickey's valiant nature often pits him against villains that try to hurt his friends and allies or conquer worlds. He is especially antagonistic towards Maleficent, with whom he has clashed multiple times, and towards Master Xehanort, whose actions have caused a great deal of pain and destruction throughout the worlds, including the ruining of the lives of Terra, Aqua, and Ventus.

Abilities
While only being a few feet tall, King Mickey is an incredibly powerful Keyblade wielder, as shown when he defeated three Darkside Heartless in a single blow just after the battle with Ansem. King Mickey is extremely skilled with a Keyblade, and the only one of two Disney characters that are able to wield the weapon. He uses his size and agility to maximize his advantages and wear down his foes, flipping and spinning attacks, and finishing them with wide strokes of his blade. It is possible to assume he gained his abilities from his training with Yen Sid. It's also known that Mickey has used two Keyblades: Star Seeker and the Kingdom Key D, a Keyblade of the Realm of Darkness. Due to his small size, Mickey has also shown to have great agility, as he is usually seen doing back flips while using his Keyblade. King Mickey wields his Star Seeker in Kingdom Hearts coded, just as he did in Kingdom Hearts Birth by Sleep. Mickey is probably the strongest proponent of the Light, although his devotion to it is eventually tempered by his friendship with Riku.

In terms of magic, Mickey is also very apt. Kingdom Hearts II demonstrated Mickey's ability to use "Pearl," a clearly light based spell, and "Holy", the ultimate light magic. In Kingdom Hearts Birth by Sleep, he is shown to heal Ventus with Cure after Vanitas beat him. In Kingdom Hearts 3D: Dream Drop Distance, Mickey is shown casting Stopza, freezing everyone in Where Nothing Gathers in time.

Mickey is very able outside of combat, as well. He has spent a large amount of time in the Dark Realm, and his Dark Realm Keyblade, the Kingdom Key D, is a polar opposite to Sora's Light Realm Keyblade, the Kingdom Key. As a testament to his heart's strength, Mickey has never once fought with his inner darkness. He can travel easily within the Corridor of Darkness and seems to be completely unaffected by it. Based on Ansem's Reports, Mickey is said to have discovered the properties of Gummi material and used it to travel to other worlds.

D-Link
In Kingdom Hearts Birth by Sleep, Mickey becomes a D-Link for Ventus and Aqua. While using him as a D-Link, they can either create an aerial attack or release multiple spheres of light to inflict damage on the enemy.

Kingdom Hearts: Chain of Memories
The King appears in Kingdom Hearts: Chain of Memories as a friend card in Reverse/Rebirth.

This card summons King Mickey, who heals Riku, stuns and deals damage to all enemies, and reloads Riku's deck. Stocking multiple of these cards creates the MM Miracle sleight, increasing the amount of health restored and damage done to enemies. Amongst using enemy cards with healing effects, such as Oogie Boogie, Mickey's friend card is one of the few methods in which Riku can heal. In Kingdom Hearts Re:Chain of Memories, Riku has two new sleights. He can perform the Holy Burst and Inverse Burst Sleights with King Mickey, in normal and Dark Mode respectively, in which Mickey hovers and shoots orbs of light from his Keyblade.

Kingdom Hearts 358/2 Days
King Mickey is playable in Kingdom Hearts 358/2 Days's Mission Mode, wearing his Organization XIII cloak. To unlock him, the player must complete every mission, which will make the item "Return of the King" available from the Moogle shop. Purchasing it will unlock him. He wields both the Star Seeker and the Kingdom Key D, along with several upgraded forms of the latter.

He has rather low HP, average strength and attack speed but excels in the Magic and Critical areas. He uses his small size to his maximum advantage, swiftly evading enemy attacks while exploiting enemy openings likewise with wide, fast strokes of his Keyblade. His Limit Break is the Holy technique that he uses in Kingdom Hearts II.

Kingdom Hearts II
In certain battles against bosses, if Sora is defeated, an alternate menu option will appear. Instead of the normal "Continue" and "Load Game," Sora is then given the options "I won't give up!" and "It's all over..". If the former is chosen, the player will be able to play as Mickey temporarily. This can happen a number of times in one battle.

In battle, Mickey can perform two attacks: the first being simply Attack, and the other being Pearl, a magical attack that damages the opponent with a homing ball of light. Like Sora, allows the player to jump and  performs reaction commands. However, Mickey's can use a Reaction Command to slowly charge his Drive Gauge, and the process is sped up during MP Charge. Once the Drive Gauge is full, Mickey can activate Healing Light, which will fully recover Sora's HP, MP, and Drive Gauge as well as switch the player back to Sora. If Mickey is defeated before using Healing Light, Mickey will instead use a Hi-Potion to heal Sora so that he regains half of his HP, although his MP and Drive Gauge will remain the way it was before he was defeated.

While Mickey can deal damage, it is impossible to actually defeat a boss as Mickey due to the fact that he lacks a finishing move. However, Mickey is very powerful and one could use him to damage the boss to the point where Sora need only land a finishing blow to finish the battle after reviving him.

King Mickey can be playable during the following battles:
 * Shan-Yu
 * Thresholder and Possessor
 * Shadow Stalker/Dark Thorn
 * Cerberus
 * Hydra
 * Blizzard Lord and Volcanic Lord
 * Storm Rider
 * Xaldin
 * Grim Reaper (Battle 1)
 * Armored Xemnas (Battle 1)

Origin
Mickey Mouse was created by Walt Disney and Ub Iwerks in 1928. Although it is commonly thought that Steamboat Willie was his first cartoon, it was actually Plane Crazy where he made his debut six months before. The reason for this is that Steamboat Willie was the first cartoon Mickey appeared in which had sound, as well as Mickey being characterized very differently in Plane Crazy. Since then, Mickey Mouse has become one of the most recognizable symbols in the world, existing for over eighty years.

On May 18, 2009, Mickey's original voice actor, Wayne Allwine, passed away from complications due to diabetes. Kingdom Hearts 358/2 Days became the last work in which Allwine provided the voice of Mickey Mouse (and his final performance overall), and the English versions of the game were dedicated in his memory. Mickey is now voiced by, who gave his first full performance as Mickey in Kingdom Hearts Birth by Sleep, and later voiced him in Re:coded, Dream Drop Distance, and the HD ReMIXes.

Notes and references
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Mickey (Rétro) Micky (Retro)