ChuChu Rocket! – 1999 Developer Interviews

ChuChu Rocket! – 1999 Developer Interviews

These three interviews, starting with an interview from Dreamcast Magazine vol 35 (1999), cover the making of Sega's 4-player party-puzzler Chu Chu Rocket, an outwardly simple game that served as a template for several pioneering technical efforts for Sonic Team, including full online multiplayer on the Sega Dreamcast and extensive single-cartridge multiplayer functionality on the Game Boy Advance.

Yuji Naka - Producer
Sachiko Kawamura - Character Designer
Takafumi Kaya – Main Planner

Naka: Right now, Sonic Team is brimming with youthful energy. Most of the staff members with any degree of seniority were sent over to Sonic Team USA, so the average age of the Japanese team has gotten a lot younger (laughs). In fact, Kaya, the lead planner of Chu Chu Rocket, is a new employee who joined Sega just this year (laughs). That doesn't mean he's unskilled at his job, however.

—It seems like the number of staff on this project was quite low, correct?

Naka: We had to increase the number of developers slightly during the latter half of development, for matters related to the matchmaking and other programming tune-ups, but the maximum number of staffers was around 13—if not for those late reinforcements, the number of key staffers would have been quite small (laughs).

Yuji Naka (1999)

Development on the game started in May, so the total production time was around 4-and-a-half months; the development period was reduced to a fraction of our usual timetable, and the budget was also significantly lower, but I was confident that we could successfully produce something in that timeframe that captured the essence of fun.

—Did you plan on making a puzzle game from the beginning?

Kaya: Rather than a puzzle game, the initial concept was to make a game guaranteed to bring out the frantic, slapstick fun of playing with 4 players.

—Were you thinking about online play as a component from the beginning as well?

Naka: Once we'd reached the point where four people could play against each other, we started thinking, "it'd be even more fun if people could connect to each other online…" and after some trial-and-error along those lines, the results were encouraging enough for us to commit to online play.

—The screen layout is fairly simple, though...

Kaya: That particular element's at odds with the rest of the game (laughs). The graphics are fully modeled in 3D, so at first we tried to give the game a more modern look by showing the screen at an angle, but that slanted angle hurt the readability of the screen and made it hard for people to really dig into the game. So for the sake of focusing on the fun factor, we adopted a more classic 2D perspective.

Chu Chu Rocket's results screen gives away the true 3D nature of the game's outwardly simple top-down stages. (source)

—Where did the cat-and-mouse theme come from?

Kawamura: At first, there were a lot of ideas floating around—ants and elephants, deer and lions, etc.—but the most intuitive way to communicate the idea of "things to chase, and things that do the chasing" was with cats and mice.

Naka: Now that you mention it, we had aliens attacking humans in the beginning (laughs).

Kaya: Yeah, we tried stuff like that, too (laughs).

Naka: (to Kawamura) In the end, did you end up designing anything other than cats and mice?

Kawamura: Yeah, the rocket! (laughs)

—So, uh, why space mice and rockets, exactly?

Kaya: Well, we came up with those details later, but the ultimate purpose was that we thought it'd feel great to punctuate winning a match or solving a puzzle with a rocket blasting off. (laughs)

Kawamura: I do remember that we'd been thinking about changing the title of the game to "Chu Chu something-or-other", and once we settled on "rocket", the designs changed quite drastically.

Sachiko Kawamura

—What was the most difficult part of the design process?

Kawamura: I drew a ton of different designs, so I ended up doing something akin to a character survey where I asked high-school girls to pick their favorites from a variety of different options (laughs). It was interesting to get a glimpse at what girls of that age currently find trendy.

—On a related subject, I'm sure Sonic Team fans will be happy to see Chao and [NiGHTS'] Pians making an appearance—do you have any tips on how to unlock them?

Naka: Unlocking Chao is pretty easy, I think—if two people work together, it shouldn't take longer than a few dozen minutes. At the trade shows, we saw people taking on puzzles with a friend, and the addition of that two-player co-op mode is another of Chu Chu's big features.

Kawamura: At first, the puzzle mode was only for one player, but we decided to add a challenge mode that'd let two players work together to clear the game. You can solve all the puzzles by yourself, of course, but if you're not good at puzzles or not comfortable with the action element, you can ask an older brother or someone to help you out, and that's another way to enjoy the game.

—Unlocking the Pian is a little tricky, don't you think?

Naka: Clearing all the puzzles might be a long road, but if you get stuck, you can communicate with other players online. Of course, exchanging info with your friends is fine, but these are some truly puzzle-y puzzles, and our staff had a lot of fun devising all the various puzzle stages (laughs). I, too, was scratching my head as I solved each puzzle they designed, but even so, I think that over 90% of the people who buy the game will be able to see it through to the ending.

—By the way, you (Kawamura) were in charge of designing the Chao for Sonic Adventure. How do you think they turned out this time?

Naka: The Chao made for Sonic Adventure were quite extravagantly built, and that's why we were only able to have eight of them appear in the Chao Garden at once (laughs)—we pushed the Dreamcast's capabilities to allow it to display eight Chao at once. For this game, though, we've maxed out at 150 objects, so in another way, we're also utilizing the full power of the Dreamcast (laughs).

Kawamura: The original Chao model was quite luxurious, so these Chao are the "Great Value" versions. (laughs)

The "great value" Chao, an unlockable skin for the Chu Chu that can be obtained by clearing the 25-puzzle Stage Challenge mode. (source)

Naka: Technically speaking, though, it's actually quite impressive—it maintains a solid 60FPS without any slowdown, even during a 4-player game. It may not look like much at a glance, but it's like a swan's legs underwater (laughs)—the player might not notice anything special, but we're doing a lot of work below the surface, so to speak, to make sure there's nothing for the player to notice (laughs).

—How about online matches?

Naka: They're also super fast. This time, we're using the general internet rather than Dwango (servers). Until now, most network games have been played over direct connections, but this is the first game of ours that'll demonstrate comparable speeds when played over the internet. There are no connection charges, and there's very little latency; if you're with a slow provider, you may have issues, but if you're with a Sega-approved provider then the connection's surprisingly fast, so I recommend you go with one of those for the best results.

Incidentally, I recently went to San Francisco on a business trip and played online against Sonic Team back in Japan, and the experience was virtually no different from playing within Japan. That said, the US has better infrastructure than Japan.

—On that note, are there any plans for an overseas version?

Naka: We're working on that right now. However, in order to play with people from all over the world, we have to think about how to handle Europe and other places where the network environments are very different, so that's something we're currently contemplating. That said, I don't think there are many games that let you play real-time, 4-player online games with people in remote locations, so it's definitely something I want everyone to be able to play.

The Japanese controller bundle for Chu Chu Rocket, which allowed players to grab the game and an exclusive controller at a very affordable price. The later North American release would be sold at a budget price, albeit without a controller bundle, and the European release would be given away for free to subscribers of Sega's Dreamarena online service.
Chu Chu Rocket (GBA) - Developer Interview (1999)

originally featured in a 1999 issue of Game Hihyou magazine

—Sonic Team's latest game, Chu Chu Rocket, looks to be a game that takes full advantage of the Dreamcast's modem to demonstrate the fun of 4-player online battles. Prior to this, Sonic Team released Sonic Adventure, and you're currently working on Phantasy Star Online; all three games feature online functionality, so I'd like to discuss Chu Chu Rocket with regards to how it uses the network. To start with, Chu Chu Rocket is a single-screen game that nowadays might strike people as very simple compared to other modern games (laughs), so please tell me how you came up with the idea for this project.

Naka: Chu Chu Rocket began development with the idea of creating a chaotic, "slapstick" 4-player game. We wanted to make sure the game wouldn't be unbalanced for any one player when playing with a full 4 players, so we tried to contain the play field onto a single screen; we did try showing the stage from a tilted perspective in order to make it look more 3D, but that added elements of unfairness where players couldn't always see everything clearly, so we settled on one locked, overhead perspective that clearly showed the entire play field.

The concept behind development was to produce something that'd offer simple, immediate fun, make something as inexpensively as possible, and to make something that would let us dip our toes into online networking. From the creators' point of view, there's seemingly no limit when it comes to making an online game, so if we dove head-first into a game like Phantasy Star Online, there's no knowing when it would end (laughs). We have no experience when it comes to making full-scale online games, so we couldn't really grasp the full extent of the Dreamcast's capabilities when it comes to running a game of such magnitude while handling the load of online connectivity.

To that end, Chu Chu Rocket was designed to allow us to get a clear indication of how many people could play online and how to work around factors like latency. Even so, despite the fact that we set out to make something "simple", we ended up flexing the full capabilities of the Dreamcast: we supported four controllers and online play, and while the game looks 2D, it's built with polygons and utilizes the Dreamcast's graphics functions to their fullest. The programming is working frantically under the hood to ensure that there's no slowdown with so many Chu Chus rushing about… this little 2D game represents the culmination of many different technological feats (laughs). We learned a lot about network development during the making of this game, and through working on a game with such an experimental vibe as Chu Chu Rocket, Sonic Team has definitely sharpened their skills.

—How long did you spend working on the game, and how many people were involved?

Naka: I can speak for the entire game industry when I say that nowadays, game development often takes too long and requires a huge number of people and in many cases, games can't turn a profit in spite of all the resources that went into making them. With Chu Chu Rocket, I decided to pursue an experimental title while keeping costs as low as possible. The development period was around 4 months and, roughly speaking, the core game was built in around one-and-a-half months, with the rest of the development period spent polishing up the network functionality and making small balance tweaks.

The size of the development team was in the range of 10 people; during the final stages of development on Sonic Adventure, staff among Sonic Team gradually started to understand the need to work on something smaller and more immediate, and so when the idea for Chu Chu Rocket was proposed, we decided to go ahead and make it.

The game was very easy to make because everyone shared an identical understanding of the game, and spontaneous, "what if we tried this…?"-type ideas could be immediately tried and adopted on the spot. Take the puzzle mode, for instance: at first, we were only thinking of the game in terms of the four-player online battle mode, but when we started thinking of how to utilize the arrow system in order to solve puzzles, it turned out to have quite a lot of depth.

What's more, as the staff was creating puzzles, we discovered that the process of making puzzles was fun in and of itself, with people constantly sharing and comparing—"how about this one?", "oh, isn't this tough?" (laughs) From there, we decided to add a puzzle editor so that players could create their own puzzles, and then when we realized it'd be fun for people to be able to upload their puzzles and download other peoples' puzzles, we added some extra communication functionality as well. The person in charge of that work thought it was a hassle, but everyone was so into making puzzles that they were like, "okay, let's get it done" (laughs). Even as I talk about it now, I think going that extra mile was the right call.

This channel chronicles Sonic Adventure's downloadable events which, thanks to the works of intrepid fans, can now be accessed through the game's in-game browser once more on authentic hardware.

—By offering that functionality right from the beginning, the players can expand the realm of the game all on their own.

Naka: That's the fun of the Internet, right?

—Have you been wanting to make internet games from the beginning?

Naka: Yes, I have. When the Dreamcast was being designed, I was the one asking them to include a modem (as standard), and I really wanted our first game to be a network game. However, Sonic Team was on a mission to create a new Sonic game, so I thought about how to use upload/download functionality to incorporate fun network features into that game, which led to it being possible—albeit via the browser—to download new content that would alter the game, share your scores on the world rankings and chat with other players; it was all very rudimentary, but also a first step for home hardware.

After that, we started researching into how we might approach something that allows players to connect directly with each other, and that led to Chu Chu. There were other puzzle concepts in discussion, but I thought that madcap struggle to accurately place arrows during local play would be a great fit for online battles; in the beginning, I was worried that the internet might be too slow to handle the game, but I was surprised that the game held up even during real-time online play.

—When you play overseas-made online games like Ultima Online, you can tell that the game systems have been designed to account for a certain degree of latency, and I think Chu Chu Rocket was also constructed with that same consideration for network conditions.

Naka: There aren't many studios in Japan producing network-centric games, and we were also groping in the dark. For Chu Chu Rocket, that delay between pressing the button and seeing the arrow placed on screen does add another interesting wrinkle, in that it adds a little strategy by encouraging players to think ahead… that said, it shouldn't come out too slowly, and between players using Sega providers, the delay between pressing the button and placing the arrow should take about 0.3~0.4 seconds. You can play using other ISPs, of course, but sometimes you might wait upwards of 0.5 seconds per button press, depending on which line your provider decides to assign you at any given time. That's just a consequence of Japan's current internet infrastructure, so it's not something we developers can really mitigate. I'd prefer that people play through Sega's supported providers where possible.

—Did you intend for users to play over the internet from the very beginning, rather than using dedicated servers a la Sega Rally 2?

Naka: Yes—we knew from the start that we wanted to broaden the audience and scope for the game. We had concerns about the expense of being billed for direct connections, and we wanted the game to be playable online across the world, if possible. Incidentally, at the end of September of this year, I went on a business trip to San Francisco, where Sonic Team USA is located, and we played a match of Chu Chu Rocket between San Francisco and Japan—even when connecting across the Pacific Ocean, the experience felt almost the same as playing within Japan. I really want to expand the reach of the game all over the world.

Dedicated players have also restored the online multiplayer functionality of Chu Chu Rocket and many other Dreamcast games via multiple methods, including the Raspberry Pi-based tunnelling service DreamPi.

—Let's talk a little about the game system itself—I thought assigning the placement of the individual up/down/left/right arrows to the four face buttons was a very elegant bit of interface design. Where did you come up with that idea?

Naka: At first, I thought we should go with a one-button system, a la Sonic Team's previous games, and have the arrows change direction each time you pressed them, but given the chaotic, split-second feeling we were going for, it wouldn't be fun if players could change the direction of an arrow once it was placed—in Chu Chu Rocket, you want to be placing down arrows gracefully, one after another, and if you accidentally make a mistake you have to quickly slap down more arrows in order to remove the errant arrow, and that impatient rush to recover from a mistake factors into the strategy of the game, while also bringing out that slapstick-esque "arghhh!!" sensation we were going for.

—Regarding the network functionality, there's a little concern that we may not be able to immediately connect to the internet whenever we might want to play. What kind of connection method does Chu Chu Rocket use?

Naka: In Chu Chu, once you enter a lobby and join a game, the connection with the server is dropped and the networking is then handled entirely by each players' Dreamcast. It's possible for players to jump into empty lobby slots while a game is being played, and it can handle thousands of parties playing simultaneously. Servers are perceived as being expensive, high-maintenance ordeals, but we wanted to prove that even a light, low-cost server implementation could be effective for online games. Of course, until we actually release the game and see users playing, we have no way of knowing whether our experiment was or wasn't successful.

—Over the course of this discussion, I see that you've really packed a lot of ideas into Chu Chu Rocket.

Naka: Actually, the basic system only took a week or two to nail down (laughs). Thanks to the simplicity of that system, it became very easy to tell that the game was becoming more and more interesting the closer it came to completion. The vibe among the development team was very reminiscent of when I joined Sega sixteen years ago; on top of everything else, it's rare to develop a game that so closely actualizes the original concept. For all those reasons, I think Chu Chu Rocket turned out to be quite an interesting piece of work.

—I sincerely hope a lot of people try it out! Thanks for your time.

A rare ChuChu plush, released as part of a series of turn-of-the-millennium Sega plushes that included characters from Space Channel 5, Rent-A-Hero No.1 and  Pro Yakyuu Team o Tsukurou! (source)
Chu Chu Rocket (GBA) - Developer Interview (2001)

originally featured in the 2001-10 issue of Dreamcast Magazine (JP)

Takafumi Kaya (Main Planner)
After joining the company as a fresh graduate, he was suddenly put in charge of the Chu Chu Rocket project and has been in charge ever since. "The key phrase for the Game Boy Advance version was 'challenge the global brain-trust', so if you can't beat it, the Dreamcast users of the world all win (laughs)."

—How did you initiate plans for the Game Boy Advance version?

Kaya: Around October of last year, there was talk that "Sonic Team is about to take on the Game Boy Advance!", and Yuji Naka san was also saying "I want to support the 4-player single-cartridge multiplayer feature", so it was decided that Chu Chu Rocket would be an ideal fit, as it's a four-player battle game and well-suited to the portable format. That said, the actual development period was just three months, so it was tough going.

—What are the strong points of the GBA version?

Kaya: Simply porting the game as-is isn't that fun, so we did our best to add original elements wherever possible. Because the GBA is something you can play wherever you go, aside from the obvious 4-player battle mode, I thought it more important than ever to allow a single person to play alone for long periods of time; Dreamcast players from all over the world had created around 17,000 custom puzzles, so we've carefully curated 2,500 of those puzzles and included them here.

Takafumi Kaya (2000)

—Wasn't it tough to pick and choose which ones to include?

Kaya: Uh-huh! (laughs) At first, I was sure it'd be impossible, but the verification process was so fun that I ended up thoroughly reviewing them all. The names and contents of each puzzle were thoughtful, and the intent of each author was properly conveyed as I played each puzzle. Once I'd checked 5000~6000 puzzles for myself, for the sake of maintaining a uniform standard of quality for each puzzle, I decided to review every last one on my own. (laughs)

—How did you decide which puzzles made the cut?

Kaya: I chose them based on various criteria, but even if a certain puzzle was very challenging, if the design was run-of-the-mill, I left it out. To be honest, there are puzzles that don't even require you to put down panels, that you can clear just by starting them (laughs), but those puzzles are interesting in their own way, so I deliberately threw them in as a "coffee break" between other puzzles.

—What difficulties did you face when porting the game to GBA?

Kaya: First off, fitting the game within the ROM, and then adjusting the game balance for 4-player multiplayer. We've added new events to the battle mode that are unique to the GBA version, like "Blindfold the Winner" and "Night Time", but we had to make sure those new elements wouldn't disrupt the finely-honed balance of the DC version. Also, seeing as we're working with fewer buttons this time around, we went through a bunch of different configurations and settled on a three-button control scheme.

Additionally, even though the GBA version is a completely offline game, I think the fact that it fully incorporates all our network know-how is what I personally find most exciting: we reflected the opinions and feedback from players who've won over 6,000 online battles, we were the first developer to support 4-player, single-cartridge multiplayer, and we've included puzzles from all over the world.

Chu Chu Rocket's catchy and surprisingly grisly lo-fi commercial—a commercial so nice that they reused it for the GBA release with minimal changes.

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