Mickey Mouse

Mickey Mouse, formally referred to as The King, Your Majesty, or King Mickey, is the king of Disney Castle and a Keyblade Master.

Mickey was 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. 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 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.

Personality
As king of Disney Castle, Mickey is 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, making sure to keep his promises. When he sees his friends get hurt, he becomes surprisingly serious and angry, such as during the battle in Hueco Mundo.

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.

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 outfit consists of a black, hooded jacket that he keeps unzipped, with short sleeves, silver buttons, and a checkered pattern at the hem. Underneath, he wears a grey shirt with a V-neck. He also wears red cropped trousers that are hemmed with the same checkered pattern as the jacket and yellow and grey shoes.

Biography
Mickey is the king of the Disney Kingdom, ruling it alongside his queen, Minnie Mouse. He eventually sought teaching under the sorcerer, Yen Sid, and became a Keyblade Master.

Mickey would later take notice that the darkness was increasing at an alarming rate. Mickey realized that the Heartless were devouring the hearts of many worlds. Hoping to stop them, Mickey entered the Realm of Darkness and find its Keyblade in order to seal the Door to Darkness. However, as this task would requite at least two Keyblades, Mickey leaves a letter instructing Donald and Goofy to head to Traverse Town and find "the Key". Shortly after Ansem, Seeker of Darkness is defeated, Mickey and Riku arrive at the Door to Darkness to help Sora 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.

Sometime later, Mickey would meet with RIku in Castle Oblivion, accompanied by DiZ. Mickey lends his support to Riku as he faces Ansem on his own, promising to come to his rescue.