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Final Fantasy Creator Suggested Kingdom Hearts To Have Complicated Story, Tetsuya Nomura Revealed
https://wccftech.com/nomura-kingdom-hearts/

Tetsuya Nomura revealed that it was Final Fantasy series creator Hironobu Sakaguchi who suggested the original game’s story to be more complicated.
In the beginning, Nomura wanted the game to be a simple adventure where the main character defeated a witch.
Sakaguchi then told him that it wasn’t a good idea and that he had to create a story that Final Fantasy fans would like.