Venerusa is a world that exists in a space of distortion. Bathed in the light of waves of Spiritus, the hearts and minds of people and dragons become one.

So begins the Heaven Era. The Aeon Group is behind the rise of the competitive sport of Dragon Racing that excites and inspires the people, while racers compete for the highest honors and influence that come with victory. Or, perhaps, they have promises to fulfill...

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Koichi Ishii


Koichi Ishii's career in gaming began in 1989 at Square Co. (SQUARE Co., LTD.) He has had a guiding hand in a variety of games, including the Mana series—his own creation—and several Final Fantasy titles. In 2007, he formed and helmed Grezzo Co. Ltd. As CEO, he continues to lead with a hands-on approach by producing and directing brand new titles.


Kyoji Koizumi

Sub Director/Planning Director

Joined Square Enix (formerly Square) in 1991. Worked most notably on the Romancing SaGa series. Starting with Romancing SaGa 2, has spent 30 years working on various aspects of games, from mechanics (particularly battle systems) to worldbuilding. Has been at Grezzo since 2007.


Shinji Takeda

Technical director

2010: Line Attack Heroes / 2011: The Legend of Zelda: Ocarina of Time 3D / 2012: The Legend of Zelda: Four Swords Adventures / 2017: Ever Oasis / 2019: The Legend of Zelda: Link's Awakening


Tatsuya Awata

Art Director

Entered the gaming industry while still in university, working part time for Sony Computer Entertainment (now Sony Interactive Entertainment). A few companies later, he was one of the founding members of Grezzo in 2007. After starting as a 2D artist, his resume now includes work on background models, character models, UI design, and even video editing. He's currently working under the jack-of-all-trades title of Art Director, though he primarily focuses on character modeling.


Kazuyuki Miyamoto

Game Cycle Lead

Joined Grezzo after cutting his teeth at SEGA and Square Enix, and has been involved in Ever Oasis, Flower Town, The Legend of Zelda: Ocarina of Time 3D, and The Legend of Zelda: Four Swords Anniversary Edition. With a focus on original titles, he is working hard to become the "ultimate jack-of-all-trades" by contributing to level design, gameplay flow, internal processing design, and more.

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    picture of producer-director Koichi Ishii

    Koichi Ishii


    • Where did the concept for JET DRAGON come from?

      I was inspired by the Red Bull Air Race World Championship. Watching it on TV, I found myself thinking how interesting it would be if it were dragons racing. I've had a passion for dragons since my time working on Final Fantasy I and always wanted to build a game around dragons. So "Air Race" was the triggering factor for this project, I think.

    • I daresay the dragon's you've created have a good deal of backbone.

      I've always loved the handbooks and illustrations for D&D. Concepts such as that of colored dragons skewing to evil while metallic dragons are inclined to the side of good made a strong impression on me. I've always been struck by the image of dragons in flight as the coolest, most suave representation.

      Though scenes of dragons battling it out with their breath weapons mid-air come to mind easily, I felt that the more noble form of dragon battle would be racing rather than a vicious life-or-death struggle. Racing is like a clash of spirits, and what's more battle-worthy than that? As the dots began to form and connect one after another, this elegant game of dragon racing came together naturally.

      dragonet design image
    • How interesting. Would you say that D&D is a constant influence behind your ideas?

      Well, dragons don't exist in actuality, but whenever I read over the D&D handbooks, dragons were alive in my mind. The desire to bring dragons to life as the central characters in a game has been an aspiration of mine since I my formative years. It's something I've always wanted to do.

    • Thanks for that insight into your passion for dragons. On that note, could we hear more about the "dragon racing" in JET DRAGONS?

      When I contemplated the beauty and vitality of dragons, I kept coming back to scenes of dragons in flight, so I delved into why that was. It comes down to one thing: Their skeletal structure.

      egg design image design image of race dragons
    •'s not about the dragons but about their skeletons?

      What I want to portray isn't just regular old dragons flying about, but different races of dragons defined by their own unique bone structure. Once your have a clear image of a dragon's skeleton, it becomes obvious how their musculature should be formed, bringing the whole silhouette to life. Then, there's the question of why dragons have breath weapons. I had this image of them having a concentration of "breath" stored up in the backs of their throats like mucus that would interact with gas to erupt from their mouths. With that in mind, I thought it would be interesting if they had pipes other than their windpipes connected by gas valves that would allow them to eject their breath from elsewhere, like jet streams from the backs of fighter jets. I imaged that the accumulated breath and gas would be like jet fuel. In other words, the dragons you see in JET DRAGONS are distinct. They're jet dragons that can exceed the speed of sound.

    • Come to think of it, isn't this the first mobile game from Grezzo?

      I've been intrigued by mobile games and wanted to create something simple. Phones have become a tool that adds to the diversity of play, so I wanted to make a proposal that would be on-hand to be played on the daily. At the same time, I wanted an opportunity to increase experience developing with Unity.

    • There you have it! Before we finish, is there anything you would like to say to those playing the game?

      Right on time. (laughs) Though this game is about dragon racing, it's not the typical real-time racing game formula. There's no movement function. Rather, it hinges on the element of the timing to press the buttons to use drifting and nitro functions. If you're one of those people who thinks, "I'm no good at racing games," or "I'm not interested in racing," then I hope you'll give this game a shot.

    • Personally, I'm the type to wind up driving in reverse in a go-kart, so I appreciate the lack of a need for realistic driving skills! (laughs)

      Aside from that, this game is really about management. In contrast to the look of it, it's actually a simulation game. (laughs)
      To sum it up, it's a "dragon-rearing race simulation game," or something along those lines...

      The core is about management and how you rear up your dragons and train your riders to secure the win. What combinations of rider and dragon will you use, and how will you strategize? That's all up to the player.

    • Rather than an unpredictable outcome based on controls, it all comes down to preparation.

      The dragons and riders have a base known as the Tower Ship. To stay on top of your team's funds and their training regimens, you have to manage all of the facilities in the Tower Ship.

      It really does boil down to management in the end. Saying that, some people might think it's too much work, or seems too difficult, but by playing on through the game, everyone should be able to enhance their management skills to bring themself the satisfaction of personal growth.

      It's quite a niche game, but those who are intrigued should give it a try.

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    サブディレクター・プランナーリード 小泉今日治の写真

    Kyoji Koizumi

    Sub Director/Planning Director

    • Can we ask which aspects of this project you're overseeing?

      I oversee the design of the game systems, and the computing and processing for all of the races, as well as for the dragon and rider growth systems. I also oversee the scenario...
      The scope of a sub director's job is quite large actually, so I might have forgotten some other things as well.

    • From a developer's perspective, what are this game's selling points?

      In just a short game session, players can challenge themselves on courses designed to showcase the unique points of riding dragons, and enjoy pursuing better scores, all with easy-to-use controls.
      There's also a generational breeding system, which offers the fun of breeding dragons that will end up stronger or better suited to the player's control style.
      I think the challenge of finding the right balance between those aspects, as well as the fun players can have raising the dragons just the way they like, will offer lasting entertainment.

    • So it sounds as if strength isn't determined by the dragon's level alone, and improvements are passed down across generations as well.
      By the way, were there any influences for the game's design or world?

      For the gameplay, we looked at flight simulators, as well as horse racing and breeding games. As for the world itself, per Ishii's suggestion, we looked to Anne McCaffrey's "Dragonriders of Pern" series for the basic setting.

    • JET DRAGON certainly is unique, in both its game mechanics and its world.
      What was it like to develop?

      That's a good question...
      We had to build an RPG-esque growth system and incorporate light action elements in the racing gameplay that were influenced by that system. As a result, we faced a lot of difficulty ensuring there was a satisfying feeling of growth in both of those areas, while also avoiding creating races that could be broken by disparities between ability levels.
      But, personally, for as tough as the process was, I think it feels equally rewarding to have made this game.

    • People can definitely lose interest when power creep becomes a factor.
      Before we wrap up, is there anything you'd like to say to everyone enjoying the game?

      JET DRAGON has had a successful launch, but we also have at least two major updates planned, including additional scenarios. I'd be delighted if you all joined us for the journey ahead.

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    Shinji Takeda

    Technical director

    • Please tell us about your role in this project.

      As the technical director, I was involved with the planning of every aspect of it.

    • From a programmer's perspective, what are this game's selling points?

      It has the kind of racing action that you can only get from dragons.

    • JET DRAGON really is a game with simple controls but a wide breadth of strategy.
      Now, Grezzo is not usually thought of as a company that makes smartphone applications. Did you gain any special insight while developing this game?

      [I learned about] the iOS and Android OS development platforms.

    • So there's quite a difference between developing a smartphone app and a traditional video game?

      You have to guarantee performance on a lot of devices. In addition, there are a variety of specs across different devices, and screen resolutions vary as well. You have to ensure that the game is comfortable to play on every device. And because the app has to run on top of the system OS, you can't make full use of the device's CPU and memory.

    • Interesting. Apart from the development environments, did you encounter any other difficulties while creating Jet Dragon?

      As far as the game design goes, our plan was to keep it pretty simple, with dragon races involving only stamina management using screen touches, and training that wasn't too complicated. However, finding the perfect balance between the training and the racing gameplay took a lot of trial and error, and we put a significant amount of time and effort into it.

      We used Unity, so there wasn't much trouble on the technical side, but we did have issues with long load times, overheating, stuttering, etc. on various devices. These are issues we don't often encounter during console development and it took us some time to resolve them.

    • If you had to spend time ironing out unexpected issues that came with the new challenge [of mobile development], does that mean there were things that you had no choice but to cut?

      I wanted to increase the number of dragons that could participate in races. In fact, I wish we could have designed the races to allow for a maximum of around twenty dragons per race.

    • Thank you for your time! Finally, could you please share a few words for all the players at home?

      Have fun racing those dragons!

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    Tatsuya Awata

    Art Director

    • Please tell us about the scope of your responsibilities as art director.

      Although I'm not always creating game assets directly as a designer, I've been involved in just about everything, including communications with external companies. I wasn't acting alone, of course, but I was very involved in every aspect relating to the game's art, including planning the art style during the beginning stages of development, developing prototype models and effects, and overseeing quality when the time came to develop the final versions. I also created promotional videos and still shots before release.

    • We've asked other members of the team about the game itself but, as its art director, could you tell us what you consider the game's strong points?

      On the visual side, the art isn't fully photorealistic nor cartoonish. By that I mean the art style pursues a realism that straddles the line between natural and unnatural, while striking a balance between detail and simplicity. ...Maybe I'm playing it up too much. It might sound a little awakward for me to be the one saying that but what I mean by a balance between detail and simplicity is that the art was designed both to ensure players could take in all the information onscreen at once, and to create a sense of space in the world. At the same time, there are also details that can be appreciated if you zoom in. We had these points in mind from the early stages of development.
      Of course various elements of design are a matter of taste, but I personally feel like we did a good job in bringing everything together.

    • "God is in the details," as they say. Were there many things you had to give up on including due to this being a smartphone application?

      There were more than a few presentational aspects we had no choice but to cut during development in order to meet the minimum quality requirements of some lower spec devices. In those cases, we had to figure out how to implement something that looked similar without becoming awkward. This isn't something unique to designers, but something every member of the development team has to worry about. On top of that, our team didn't have much experience with the engine we used for development—in fact, we were all starting practically from scratch—so that was another struggle we all shared.

    • I see. After hearing that, we can better appreciate the fruits of the staff's labor and their struggles in various aspects of the game when we play it.

      Ideally, I would have liked to create a few different models within each species of dragon, but the reality is that we didn't have the resources to spare.
      I'd like to say it might happen in a future update, but I could be playing with fire by saying that, in case it doesn't happen. Let's just say it'll depend on the response from the players.

    • Could you leave us with one final comment?

      I know the game can seem daunting, being a simulation game, but it's a perfect example of a game that hooks you more and more as you get into it. So even if you only see the hatchlings—no, I take it back—I'd like everyone to see every species of dragon if possible.
      We've paid studious attention to the game world in the art, right down to the construction of the super small rider helmets. It's the lovingly crafted art and models, like those helmets, that I'd like to focus on as we move forward with ongoing updates while building up our playerbase and community as much as we can.

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    Kazuyuki Miyamoto

    Game Cycle Lead

    • Please tell us which aspects of this project you were responsible for.

      At the very beginning of the project, we had the game planners create all the non-static game assets themselves, so I was using Unity to both program and create moving objects from the start.That was our workflow during main development, and the scope of my responsibilities spread to cover all of the mechanisms centered around the gameplay loop. These included event progression, race course planning, UI, and the flow of all the menuing and side mechanics.

    • From programming to planning, you really do wear many hats. (laughs) Having seen the game from so many perspectives, could you tell us what you consider its strong point?

      I think there are a lot of selling points, but personally, I believe the key point is that there are a variety of ways to make your team stronger as you aim to become the dragon race champion. The approach changes depending on the player's ingenuity. Or, to put it another way, the selling point is that there are many different routes to clearing the game.I hope that everyone can enjoy building and trying out their own unique teams.

    • I get the feeling that during development a lot of attention was paid to getting a good grasp of player mentality.

      Without being limited to only those in games, I really try to reflect in my work all the experiences that have moved me in the past. I think that doing that plays a part in ensuring players strongly identify with a game. I place great value on everyday experiences and am very deliberate in how I apply my own to the games I work on.

    • It must take a significant amount of craftsmanship to integrate everyday life into a game's relatability. What did you find to be the most difficult part of developing JET DRAGON?

      I guess it would have to be the hurdle of developing an original title. This is true for any new title, but when we're creating everything from the ground up there's often no easy way to determine the best course of action so we have to find those answers for ourselves.
      Until every staff member can visualize the same finished project, we all have to put a great deal of effort into moving the project forward by bringing our individual ideals into reality. The number of staff that work on a single title has only been increasing over the past few decades, so the difficulty of getting everyone on the same page has risen too.
      But at the same time, the elation when you pull it off is all the stronger, and you definitely feel like you want to make even more games! (laughs)

    • You've got a real creative spirit! (laughs) Do you have any regrets regarding this title?

      Because JET DRAGON was made to be a console-type experience, we planned it to be a game that doesn't slow down player progression and therefore can be cleared rather quickly.
      Looking at the reviews, I'm happy to see that the majority of players are satisfied with it. On the other hand, as an Apple Arcade title, I do wish the game could be enjoyed a little more casually and, moreover, for a longer time.
      What I mean to say is, I wonder if it couldn't use a few more open-ended elements to encourage long-term gameplay, such as daily missions or multiplayer. We did have ideas along those lines in the planning stage, but unfortunately we weren't able to actually implement them in the end.

    • Thank you very much! Before we go, could you please share a brief message for the players at home?

      While it's quite fun to continue playing the same file, I think it's even more fun to start a new file after you've cleared the game.
      While debugging the game, I played through it many times, and discovered more with every playthrough. For example, I experimented to see what would happen if I strengthened different attributes first, or if I focused on a stamina build, things like that. The game is really designed for players to play again from the beginning while building on past experience. By doing this, they can really feel themselves getting better at building and managing their team. I think that makes the game even more enjoyable.
      I imagine it would also be fun to make challenges with friends, like competing to see who can become the grand prix champion in the fewest number of seasons.
      So for those of you who have already cleared the game, I encourage you to try it again from the beginning!



A girl who secretly harbors a huge amount of spiritus. She gets along well with Isa,but they struggle to keep in contact since Sache was scouted by Minstrea.


A girl whose moods swing wildly. She
suffers from an inferiority complex due to constantly comparing herself with her incredibly skilled sister and best friend.


A former teammate of the legendary rider
Harvey. Curious and mischievous, he has
become noticeably more results-oriented
since taking over the Spiritus Laboratory.


A woman of noble birth and a former
teammate of Harvey. While she usually
comes across as quiet and refined, she has a definite stubborn streak.


A young protégé of Matthias, one of
Harvey’s former teammates. He was first
scouted when Matthias spotted him carrying bread home to support his family.


A former confidant of Harvey. He took over the team after Harvey’s death, but has since become preoccupied with his duties as head of the Aeon Group.


A well-known veteran trainer. Despite his untrustworthy looks, he has trained many of the best current racers. Like a father to Leovarth.


The daughter of the legendary racer Harvey. Ever since her father went missing in an accident, she has been aiming to be a top rider in order to keep a promise she made.


A slightly unrefined Muten boy. Good with his hands, he switches easily from dragon breeder to tower ship mechanic. He watches fondly over Eleanor’s progress.


An exceedingly intelligent Elfith trainer.
Bold and courageous, she shares a close understanding with her good friend Kemi.


The heir apparent to the Aeon Group. Taken in from the slums as an orphan, he rose through the ranks thanks to talent and hard work. He is oddly hostile to Eleanor.


Scale Dragon

A close relative to the founding line of dragons. Jet skills first developed from this breed. Their abilities tend to be well-rounded but boosting and breath skills are their specialty. They are mainly found along the Mytos Coast.

Beast Dragon

A species known for its mammalian build and characteristics. They are covered in a long coat and have excellent stamina. They lean toward specialty in ascents and chaff skills. Mainly found around Janna Lake.

Feather Dragon

A species with avian characteristics and build. Their coat is comprised of feathers and their speed is exceptional. Descent speed is where they shine. Found mainly in the Arbaro Forest.

Snake Dragon

A reptilian species with snake-like build and characteristics. Covered in smooth scales, they excel in acceleration and balance. Winding courses and bad weather are their forte. Found mainly in Baralack Thicket.


A species with an aerodynamic skull and body evolved for high velocity and wind resistance. Unmatched in speed. They specialize in boosting and jet skills and can be found in the Reclier Mountains.

Rock Dragon

A reptilian species with turtle-like build and characteristics. Covered in large, resilient scales, they have outstanding stamina and speed. They are extremely resistant to physical and elemental attack. Mainly found in the Shian Desert.

Fairy Dragon

A dragon species that combines the benefits of insect and fish traits and is of the rare line of fairy dragons. They are unmatched in acceleration, balance, winding courses, barrier skills. Mainly found around Immorta.


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Dragon Racing

Racing ability means everything in this world.
Set your sights on the pinnacle of the racing world with a team of dragons and racers to be proud of.

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Team Building

Your team's ability to reach their full potential depends on your chops as team owner. Give them what they need, and they'll come through.

Dragon Pairing

image of dragon paring

The possibilities are limitless!

As you continue through the game, your dragons will mate, bringing even more dragons into your lineup. The offspring will take on aspects of their predecessors' species and abilities, strengthening the line with every generation.