name some characters in this game.
Sora, Riku, Kairi, Donald Duck, Goofy, Mickey Mouse ar some of them
Kingdom Hearts
The series starts with "Kingdom Hearts", where a 14-year-old boy named Sora is separated from his friends Riku and Kairi when their home Destiny Islands is consumed in darkness. At that moment Sora obtained a weapon called the Keyblade that allows him to fight the Heartless, creatures that originate from the Realm of Darkness, before ending up in another world, Traverse Town, where he meets Donald Duck and Goofy, two emissaries from Disney Castle sent to find the Keyblade wielder under orders from their missing king, Mickey Mouse. As the three band together and travel to save various worlds from the Heartless while searching for their companions, encounter a group of Disney villains whose ability to control the Heartless was given to them by Maleficent, who enlists Riku's aid in seeking seven maidens called the Princesses of Heart whose power would open the way to Kingdom Hearts, the heart of all worlds. 
where did the idea for kingdom hearts come from The initial idea began with a discussion between Shinji Hashimoto and Hironobu Sakaguchi about "Super Mario 64" is 'kingdom hearts' a video game? Yes, a crossover between Square Enix and Disney based in a fictional universe who is the developer of this game? Tetsuya Nomura is the director and Hashimoto the producer
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Kingdom Hearts [SEP] Story
The series starts with "Kingdom Hearts", where a 14-year-old boy named Sora is separated from his friends Riku and Kairi when their home Destiny Islands is consumed in darkness. At that moment Sora obtained a weapon called the Keyblade that allows him to fight the Heartless, creatures that originate from the Realm of Darkness, before ending up in another world, Traverse Town, where he meets Donald Duck and Goofy, two emissaries from Disney Castle sent to find the Keyblade wielder under orders from their missing king, Mickey Mouse. As the three band together and travel to save various worlds from the Heartless while searching for their companions, encounter a group of Disney villains whose ability to control the Heartless was given to them by Maleficent, who enlists Riku's aid in seeking seven maidens called the Princesses of Heart whose power would open the way to Kingdom Hearts, the heart of all worlds.