Before speaking with the staff, Nomura had chosen over 20 worlds to include in Kingdom Hearts, including original worlds.

To whittle them down, worlds were chosen based on popularity, if there were interesting characters to play as, and if there were interesting places to be in, in that order.

Originally, in the scene where Sora, Donald and Goofy first meet in Traverse Town, Donald and Goofy were supposed to explain abilities and the like through singing.

When asked about what kind of song he wanted from Hikaru Utada for Kingdom Hearts, Nomura said that the song would play during the ending where Sora and Kairi parted, since the concept of the scene existed even early on in development. He stated that he didn't want to make the ending look sorrowful, but optimistic.

In Kingdom Hearts II's ending where Sora is reading the letter Kairi wrote, the word "starting" is spelled wrong. It is written: "Now I will step forward to realize this wish. And who knows, stating a new journey may not be so hard."

Due to the contract, Mickey Mouse could only be included in a single cutscene, because Disney didn't want him to be abused in order to attract attention. Their example for the type he could play was "waving from behind a large crowd."

Ever wonder why Kingdom Hearts was a heart-shaped moon? Nomura didn't have a plan for the heart-shaped moon on the cover of Kingdom Hearts. It wasn't until he asked Kazushige Nojima to write Kingdom Hearts II's scenario that the idea was born to use the heart-shaped moon in the series.

In Nojima's scenario it was written that the Kingdom Hearts Xemnas created is "like a moon that floats in the World that Never Was." When Nomura read it he thought, "Oh, this can be connected!" so Nomura decided to make the moon look like the previous game's key visual.

Out of all of the newly introduced Organization members in Chain of Memories, Nomura's favorite was Axel. Axel was also favored by the majority of the staff. Nomura described Axel's future role in KH2 as "delicious", and that his story could make you cry.

The intro scene, as well as Sora's monologue during it, is supposed to express his confusion at the world he lives in, trying to figure out if it's real or not. This was intentionally used to make the player suspicious of the worlds they're in, creating doubt as if you actually imagined it.

After arriving in Traverse Town when Goofy calls out "Pluto, we're going," Pluto is actually not present at that time. Sometime between the time he first disappears and then reappears in the ending, he met up with King Mickey. The reason he perked up in Traverse Town was because he felt the King's presence.