Q1: The Kingdom Hearts series has many intricate settings and characters. How do you consolidate these and communicate them to the team?
I don't think the team fully understands everything. For example, during recordings, sometimes the staff explaining the settings or characters to the voice actors will ask me, “This is correct, right?” and I might respond, “No, not quite.” This kind of back-and-forth happens (laughs). However, it’s understandable because I’m the only one who knows the parts of the characters that haven't been depicted yet. I personally navigate through the complex storylines, constantly swaying between different directions. On the other hand, I encourage the team to question or point out anything to me.
Q2: Do you have a sort of "bible" or documentation for the settings?
I do have personal notes to ensure I don't forget things. These include the footsteps of important characters, events that haven't been depicted yet, and future developments.
Q3: So, these aren’t shared with the team?
No, I keep them a secret (laughs). But when necessary, I sometimes write sudden bursts of detailed settings into the script to make sure the staff understands.
Q4: In Kingdom Hearts, you seem to lay out foreshadowing that spans multiple installments. How do you keep track of everything?
A lot of it is written in my notes, but I also rely on the staff to remember things. Since I enjoy watching videos, I sometimes check gameplay footage and fan theories on YouTube. Rather than relying on my notes, I often ask the staff how things played out in previous titles.
Q5: Do you watch fan theory videos? Do you ever think, “They’ve figured it out, so I’ll change it,” or “They don’t get it at all”?
I find them genuinely interesting to watch. Often, I think, “It’s not as complicated as people think.” I’m frequently impressed by how deeply people analyze things. For instance, some people try to connect Kingdom Hearts to the Final Fantasy series, but the writers for each are different, and even though I’m involved with both, there’s no connection between the titles.
Q6: At the time of the first Kingdom Hearts, I assume you didn’t have the entire current storyline planned. As the series progresses and more settings and characters are introduced, does it become increasingly difficult to maintain coherence? Do you mostly make things up as you go?
I had a general direction from the first game. As I mentioned earlier, I do take notes on future developments. When things don’t quite align with the planned direction, I make adjustments on the fly. While the details weren’t fully fleshed out at the time of Kingdom Hearts I (released in 2002), I had thought about the next few installments ahead of time. So, while we were working on Kingdom Hearts III (released in 2019), I already had Kingdom Hearts IV and beyond in mind and worked toward that.
Q7: This year, Kingdom Hearts: Missing-Link, a mobile app, is also set for release. With important story elements being released on mobile or handheld devices, are you concerned that some players may lose track of the storyline?
Yes, that is a concern (laughs). That’s why Missing-Link takes place in a much earlier timeline than the main Kingdom Hearts series. However, as fans often joke, “Even though Kingdom Hearts IV is coming out, it’s really more like Kingdom Hearts XIII” since the non-numbered titles are obviously connected. Still, I believe it allows for a deeper enjoyment of the Kingdom Hearts universe. That said, both Missing-Link and Kingdom Hearts IV are being designed with a strong emphasis on being standalone titles rather than just sequels. For instance, a new approach in the scenario writing is that I’ve had staff members who haven’t been involved in Kingdom Hearts before join the writing process. Of course, I’ll make final adjustments, but the base script was written by people unfamiliar with the series, which is why I don’t think these projects will feel like obligatory follow-ups. With Missing-Link, we’re addressing “the lost history,” so the expectation is that not knowing everything is part of the experience. If you know the lore, it’s more enjoyable, but it’s not a prerequisite.
Q8: Much like how starting a long-running manga series can be daunting, the large number of Kingdom Hearts titles poses a similar challenge. How do you plan to attract new users?
I’d love to know the answer to that (laughs). As I mentioned earlier, Missing-Link and Kingdom Hearts IV are kind of reset points for me. I felt like Kingdom Hearts III was a natural conclusion of sorts, so we’re resetting things by bringing in new writers and even redesigning the logo to make the series more accessible.
Q9: So, that’s why the logo changed.
If you’ve seen the ending of Kingdom Hearts III, you’ll understand, but the way Sora’s story ended was a way to reset things, so Kingdom Hearts IV should be more accessible than previous titles. Of course, longtime fans will recognize the familiar feel of the series, but we’re designing it to be approachable for newcomers as well.
Q10: In a past interview, you mentioned that players would spend a lot of time in “Quadratum” (a field resembling Shibuya) in Kingdom Hearts IV. Why bring in a more realistic setting to a world that was previously pure fantasy?
There are a few reasons, but I personally like settings that are slightly removed from reality rather than being completely fantastical. It’s the same with films—I find it harder to get immersed in worlds that are entirely fictional with no connection to reality. That’s why Quadratum is based on Shibuya but isn’t the real Shibuya. I’m fascinated by the idea of a slightly off-kilter version of reality, rather than a pure fantasy world.
Q11: Manga like Tokyo Ghoul, set in Tokyo, and Jujutsu Kaisen, with its Shibuya arc, are similar in that they use real-world locations. Perhaps fans of both manga and games enjoy these grounded yet fantastical settings.
That might be true. It’s easier to relate to. Additionally, I’ve always thought there were plenty of creators already doing medieval high fantasy, so I didn’t need to. In 2007, we released The World Ends with You, which was also set in Shibuya, but now many works use Shibuya as a setting. It feels like everyone has come to Shibuya (laughs).
Q12: It does seem like more works are set in Japan these days. Speaking of the mix between reality and fantasy, at the beginning of Kingdom Hearts, there’s a monologue where Sora says, “I’ve been having these weird thoughts lately… Like, is any of this for real or not?” Did you already have Quadratum in mind back then?
The name “Quadratum” didn’t exist at that time, but I had the concept in mind. It was a long-term plan that I knew we would eventually reach (laughs).
Q13: So it’s a 20-year-long payoff for that foreshadowing. Lastly, do you see the ending of the Kingdom Hearts series in the future?
To give you a realistic answer, I’m approaching retirement age, so it’s becoming a race between retirement and finishing the series (laughs). However, I am creating Kingdom Hearts IV with the intent of leading toward the series’ conclusion.
