sentences:  The most prominent of these characters is Mickey Mouse, the king of Disney Castle, who serves as a Keyblade apprentice under the sorcerer Yen Sid at this point in the series chronology.Donald Duck and Goofy, who assist Sora in most other games, appear in smaller roles.Most other Disney characters remain in their respective worlds regardless of their overall importance to the story in previous installments, such as Maleficent and Pete, who served as major antagonists between "Kingdom Hearts" and "Kingdom Hearts II", and a number of the Princesses of Heart.