Ask the Developer Vol. 18, Mario Kart World – Chapter 1
21/05/2025
Some of the images and videos shown in text were created during development.
This article has been translated from the original Japanese content.
In this 18th volume of Ask the Developer, an interview series in which developers convey in their own words Nintendo's thoughts about creating products and the unusual details they hone in on, we're talking to the developers behind Mario Kart World, a Nintendo Switch 2 game that launches alongside Nintendo Switch 2 on Thursday, June 5th.
Chapter 1: Taking it to the next level
Chapter 2: A lasting impression
Chapter 1: Taking it to the next level
First, could you briefly introduce yourselves?
Yabuki:
Hello, I'm Kosuke Yabuki, the producer for Mario Kart World. I've been involved in the Mario Kart series since Mario Kart Wii. I was the director for Mario Kart 7 and Mario Kart 8, and have been working as a producer on the series since Mario Kart 8 Deluxe. I also worked on ARMS (1) as a producer.
(1) Nintendo Switch game released in June 2017. A fighting game where players intuitively throw punches using extendable arms, controlled by holding a Joy-Con controller in each hand.
Sato:
Hi, I'm Kenta Sato, the programming director. For this game, I mainly provided direction on technical matters. I've been involved as a programmer for the Mario Kart series since Mario Kart 8. Besides that, I also worked as a director for ARMS and was in charge of programming the Wii Sports series (2). I often work on games that are designed to be fun to play together with everyone.
(2) A game series on Wii where you use the Wii Remote to intuitively play a variety of different sports. Includes the games Wii Sports, which came bundled with the console, and Wii Sports Resort, released in Europe in December 2006 and June 2009 respectively.
Ishikawa:
Hello, I'm Masaaki Ishikawa, the art director. I was in charge of crafting the game's visual direction. I also worked on Mario Kart DS and Mario Kart 7 as a character designer. I was the art director for Mario Kart 8 and ARMS.
Jikumaru:
Hi, I'm Shintaro Jikumaru. Leading the planning team, I was responsible for the general gameplay design. I've been developing together with everyone here since Mario Kart 8 and ARMS.
Asahi:
Hi, I'm Atsuko Asahi. For this game, I was the music lead in charge of arranging tracks and working on various things related to the background music. I've been involved in the Mario Kart series since Mario Kart 8. Besides that, I also composed music for games such as Super Mario Maker 2 (3), and worked on ARMS as the sound director.
(3) Nintendo Switch game released in June 2019. In this 2D platformer, players can create their own courses by combining different parts.
Thank you very much. To begin with, could you tell us a little about this new game, Mario Kart World, Yabuki-san?
Yabuki:
Of course. Mario Kart World is the first new game in the series released on a home console since Mario Kart 8 Deluxe, which launched around eight years ago. The game is set in a large, seamlessly interconnected world. In addition to races as in previous games, where you complete three laps of a course, you can also race on the roads that connect different courses or even take part in Knockout Tour races that span the game's world. In this world, you'll also be able to experience changes to the environment. This includes the time shifting between day and night and weather changes, such as rain or snow. On top of races, there's also a mode called Free Roam, where you can drive around the seamlessly interconnected world however you like.
So the various courses are interconnected. Could you tell us how development for this game got started?
Yabuki:
We were thinking about what to do for the next Mario Kart game even during the development of Mario Kart 8 Deluxe, and we began prototyping in March 2017. It was at the end of that year when we officially started work on it as a project. I felt that in Mario Kart 8 Deluxe, we were able to perfect the formula that we'd been following in the series up to that point, where players race on individual courses. That’s why, this time, we wanted the gameplay to involve players driving around a large world, and we began creating a world map like this.
Looking at this, it's easy to understand how the world is connected. And on closer inspection, you can see the level of detail that's gone into it.
Yabuki:
The higher-density areas correspond to courses like Mario Circuit and Bowser's Castle in the previous Mario Kart games. Up to the previous game, we created each course separately as an independent element, but this time, we ended up with a map like this because all the courses are connected as part of the same world. In this game, rather than taking the approach of simply increasing the amount of content and adding more variations, such as the number of courses, we wanted to completely change the concept and make it playable in a larger world.
I’d like to ask about the title first. Was it always the plan to call it Mario Kart World, rather than Mario Kart 9?
Yabuki:
If the idea had just been to add more courses, then I think we would’ve called it Mario Kart 9. But, that wasn't our approach this time. We wanted to take the series to the next level. So, we decided to drop the numbering this time and go with a completely new title, Mario Kart World. So we'd already added "MARIO KART WORLD" to the concept art from the early stages of development.
Ah, I can see it written there. You must've had a consistent vision from the very beginning if the name even shows up on the concept art. By the way, where did the idea of connecting the world come from?
Yabuki:
In previous Mario Kart games, after finishing a course, you'd move on to the next course. However, I thought that with modern technology, being able to seamlessly transition between courses and realise a single, vast world wasn't beyond the realm of possibility. So with this in mind, we set out to create a new kind of Mario Kart. ...And that's when all our troubles began. (Laughs)
So that's how you set out on your arduous journey. (Laughs) Speaking of which, what did everyone else think when you first heard about this concept?
Sato:
I was involved from the start of the Mario Kart World project, and at the time, there were a lot of games out there set in vast worlds. I've seen and heard about the difficulty of developing such games, so I was feeling the pressure and wondering if we could really do that with Mario Kart too. Also, we've always considered it important for the Mario Kart series to run at 60 fps (4), and we believe split-screen multiplayer to be an essential element. I was excited, but at the same time, I felt like it would be tough.
(4) Frames per second. This value represents the number of images (frames) that are displayed per second on the game screen. 30 fps means that 30 images are displayed per second, while 60 fps indicates 60 images per second. The higher the number, the smoother the image.
Ishikawa:
I also led the art direction during the development of Mario Kart 8, and even then, the change to HD dramatically increased our capabilities to create some very distinctive courses and lots of characters. Also, we were able to implement visuals from The Legend of Zelda and Animal Crossing in the DLC, so I felt to a certain extent, like we'd achieved everything we wanted. And that's when I heard from Yabuki-san that we'd be creating a single-world Mario Kart, which I thought sounded pretty interesting. Until now, we've only been able to express the world of Mario and other characters through different courses, so I thought this would give us a new way to portray the world and have a lot of potential. So, when I heard the concept, my excitement won out against my expectations of how challenging it would be. In a way, that was when all our troubles began. (Laughs)
Jikumaru:
I also felt that with Mario Kart 8 Deluxe, we'd pretty much perfected the formula of a Mario Kart game where each course is played separately. In that sense, I felt that a Mario Kart game where you play in an interconnected world would also be rewarding from a developer's perspective. However, from a player's perspective, it can sometimes feel particularly disappointing when a sequel changes too many things. So, as someone involved in game development, I felt that our first challenge was to figure out how to add new elements while still making it satisfying for those who've played previous Mario Kart games.
Asahi-san, you must've also had some thoughts from a sound perspective. What were your impressions?
Asahi:
“All the different landscapes are connected, and the world is expanding...what am I going to do?!”. That was my first thought. Until then, I'd been composing custom-made tracks for each course based on the weather and time of day. But now, with everything being connected and with the ability to drive anywhere, there are so many more things you need to consider. We need lots of sounds to fill the gaps between courses, and because players take different routes and drive at different speeds, we have to assume that the timing of background music transitions will vary. I thought we'd never finish development if we approached sound creation the same way as before, and I was worried about whether we'd really be able to get it done.
I see. It seems like everyone felt that this was a major change of direction for Mario Kart. What kinds of things, in particular, did you keep in mind when planning and moving forward with this new title?
Yabuki:
We were careful not to change things that have been important to Mario Kart as a series purely because it's now set in an interconnected world. As before, we needed to keep the fun of casually playing with family and friends, but also have depth, where players can hone their skills against the online competition (5).
(5) Online features for this software require a paid Nintendo Switch Online membership.
Jikumaru:
I think people who've played the series up to now are looking for a Mario Kart game that feels familiar to them, so we wanted to make sure we preserved that. This game has some new features like Wall Ride and Rail Ride, but we made sure that you could still have fun playing with just the basic controls without using these new techniques. We implemented and adjusted features with the goal of gathering up all the best bits from past Mario Kart games. During development, Yabuki-san kept saying, "Well, that's how we did it in the last game", almost like it was his catchphrase. (Laughs)
Yabuki:
Due to it being an interconnected world, we had to remake all kinds of features, and we were often discussing whether features from the last game should stay the same or be changed.
Sato:
This time, we refreshed the tools used to create the game, so everything, even the programming systems, has been rebuilt from scratch. …But Yabuki-san insisted that not only the programs and the tools be remade from scratch, but that they should be capable of producing the same level of quality seen in previous games.
Yabuki:
That's no easy task, and I often ended up saying, "I don't get the same feeling as before when I play it”. (Laughs)
Everyone:
(Laughs)
Ishikawa:
On the other hand, the direction of the visual design changed drastically. For Mario Kart 8, based on the concept of vehicles transforming to be like hovercraft, we opted for a futuristic and sophisticated design. Whereas in this game, since you're driving through all kinds of locations in the world, we wanted to convey the feeling of adventure. We also wanted to create a lively, bustling atmosphere even in a vast world, and we were talking about how we wanted to recapture that feeling from Super Mario Kart, the first title in the series. During those discussions, someone on the team mentioned the key phrase “playfulness”.
Artwork from Super Mario Kart on Super Nintendo Entertainment System – Nintendo Switch Online.
From there, we focused on creating a chaotic vibe where anything could happen, like the lively and bustling atmosphere where lots of characters are in a pack, jostling for position.
Indeed, Super Mario Kart gave the impression of drivers being crammed into a narrow course. Looking at it from that perspective, this game does have rounded edges to its visual design, like in the original game.
Ishikawa:
The characters in the Super Mario series have a rounded look, so we wanted to give the vehicles a rounded design too, to match their appearance. We also wanted to give the characters a livelier look even while they're in their vehicles, so we put everything together in a way that gives off a sense of playfulness through the combination of the characters' rounded designs, soft facial expressions, and rich movements.
Asahi:
The sound was also created based on the theme of playfulness. We revised the audio systems of the in-game space so that the sound effects convey the vast world while maintaining the lively, bustling atmosphere that Mario Kart is known for. The background music features a harmonica with a powerful tone that aligns with the idea of playfulness. It's featured in various tracks, including the main theme.
The sound also took on a cool, futuristic direction in the previous game, but this time, we increased the proportion of live instruments for a more energetic sound in an attempt to match the brighter atmosphere of the world.
Going back to the lively, bustling atmosphere you mentioned earlier, this game lets up to 24 players race each other. That's a big increase over the last game. Was this number decided at a relatively early stage?
Yabuki:
Yes, the previous game was for up to 12 players, and we decided fairly early on that this game would be for up to 24 players. By creating long routes in a vast world, you could end up with players spread out in various places, which could diminish the sense that they're racing against each other. So we figured that by increasing the number of racers, you'd be sure to see some competitive action here and there. Maybe that's a bit simplistic. (Laughs)
Sato:
At the time, we were developing Mario Kart World for Nintendo Switch, and we were analysing from a calm and collected programming perspective whether it would be possible to accommodate 24 players. In game development, you first finish making all the different elements and then optimise them to run on the system. But when trying to accommodate 24 players, we had to make all kinds of processing optimisations right from the start as we were making it.
I’m sure you'd already been making huge efforts just to create 12-player races, but suddenly being told you had to double that... If it were me, I’d be at a loss.
Ishikawa:
But I was happy in terms of the visual design because it would give off more of the lively, bustling feeling. I felt like the 12 players we had previously was a lot, but as Yabuki-san said, once players spread out, the course starts to look sparse, and the visuals give off a sort of lonely feel. So, I thought that 24 players would be better because there'd be more interaction between various players. That said, it was quite challenging once we got going and the volume of design work increased. But it was worth it. (Laughs)
Sato:
When we were developing for Nintendo Switch, it was difficult for us to incorporate everything we wanted, so we were always conscious of what we were giving up in return. We discussed things like toning down the visuals, lowering the resolution, and we even considered dropping the frame rate to 30 fps in some cases. It was a tough situation.
What did you decide to give up on in the end?
Sato:
Well…
Jikumaru:
…We couldn't give up on anything. (Laughs)
Everyone:
(Laughs)
Yabuki:
We worked on it while kicking the can down the road in terms of deciding what to give up on, so at some point, we knew it was going to get messy. But as we'd decided to release the Mario Kart 8 Deluxe – Booster Course Pass, we thought that would give us a bit more time to continue development. That's when the conversation of moving it to Nintendo Switch 2 came up, and this suddenly opened up a bunch of possibilities on what we could do. It was truly a ray of hope.
