Creator of TRiNiTY, Ryo Momoido's Game Design Story

Design Challenges on the Road to Game Market

Just one year ago, I didn’t know anything about board games aside from having played Uno and used playing cards a couple of times. I didn’t even really know the difference between board games and trading cards!

In mid-June of 2024, by chance, I started going to a bar that had lots of board games. It was there that, while playing alongside my friends, I came to realize, “Board games are actually fun!”

The thing that changed me the most happened on October 22, 2024. On that day, at my usual bar, I had a shocking encounter. A 21 year-old college student I was chatting with said, “This is a game I made, would you like to play it together?”

To me, board games were always something to be played, and I had never even thought of actually making one. On top of that, this game was made by someone half my age! Listening to his story, I felt simultaneously surprised and moved. He told me more about the process, and apparently his game was being sold at this bar, as well as online.

That night, I listened attentively to his full story. How he designed the game, what printing company he used, how he secured places to sell his game… He lit up as he told me about his path. In listening to him talk, I realized that making a game seemed like a lot of fun. I thought, “I’d like to try making a game too!”

By late November 2024, a month had passed since I decided to make a game, but I still hadn’t come up with any ideas. Then suddenly, inspiration struck. I’m a fan of Atsuhiko Nakata from Oriental Radio, and I remembered a TV show he was on over ten years ago called “Numer0n.” It was a game where players guessed each other’s three digit numbers. I thought, “What if I added card effects to this simple number-guessing game? Wouldn’t that make it more interesting?”

…and with that, TRiNiTY was born!

After that, things moved quickly. I made a prototype version using playing cards and copy paper, and playtested it with my friends and family. At the same time, I consulted with a designer friend to solidify the art direction and style for the game.

Toward the end of January 2025, the game data was finally more or less complete. “With this, I should be able to make it in time to apply for a booth for Game Market!” I thought. Sure enough, I just barely managed to apply during the second round of vendor recruitment.

Around the end of February 2025, 50 real copies of the game arrived from the factory. From there, it was all about figuring out how to make people aware of my game, so I conducted promotional activities geared toward this end. I thought making a video about the game rules and influencer marketing would be essential, so I followed many famous board game channels/accounts on YouTube and X (formerly Twitter). 

I left comments on the short videos of creators who had lots of impressions to try and get their attention. I even flew from Miyagi to Nagano to meet with a famous YouTuber to make the case for them to introduce my game to their audience. Because of these sorts of efforts, I successfully got a number of famous influencers to pick up on my game.

I did my best to post frequently on X (formerly Twitter). I didn’t just post advertisements, I shared the whole process–the trial and error, the setbacks, the behind-the-scenes prep leading up to Game Market, even the mundane packing work. I also posted about my worries, struggles, and inner conflicts. By showing uncool, unpolished sides of myself, I aimed to let followers see me gradually grow over time. I wanted to become someone they’d genuinely want to root for.

After around three months of steadily building up a fanbase through careful promotion, I went into Game Market fully prepared - even bringing along an attractive sales assistant to help at the booth. I didn’t just make and sell the game - I thought through the entire process of getting it into users’ hands and promoted it as a complete package.

The Success of a Complete Sell-Out

Thanks to the strong visual design of the packaging and cards, as well as proactive promotion I did on social media, over 90 copies had been pre-ordered before Game Market even started.

At that point, I was confident everything would sell out on the day of the event.

I brought three titles: 110 copies of TRiNiTY Standard Edition, 70 copies of TRiNiTY High-Grade Edition, and 120 copies of The Truth Behind the Samejima Incident, which was only just completed right before the event. There wasn’t any time left to promote The Truth Behind the Samejima Incident, so I made a bold post on social media: “We’re not putting this on display—if you want it, we’ll be secretly dealing it under the table!” That playful approach caught the attention of my followers, who shared the post widely. It went viral, and right before the event, it successfully built up hype and drew people in.

Then came the big day.

A huge number of customers came to the booth. So many people showed up that a line had to be formed several times—it was more overwhelming than I’d imagined. But in the end, by 3 PM, every copy of TRiNiTY was sold out. As for The Truth Behind the Samejima Incident, 116 copies had sold by that same 3 PM deadline, and we packed up the booth early. After that, we strolled around the venue and enjoyed some relaxed shopping.

Selling around 300 games in just four hours gave me a real sense of success. It was a moment that made me feel everything I’d done up to that point hadn’t been in vain. But I don’t plan to get complacent—I want to keep reminding myself that I’m still a challenger, and continue pushing forward with that spirit.

Improvements and Feedback Going Into the Second Edition

In the current first edition, players have to guess a "three-digit number." But in the second edition, the goal will be to guess “three individual numbers.”

I kept seeing players get confused when facing each other and placing their cards in the stand—people often didn’t know which card represented the hundreds digit and which was the ones digit. That’s something that’s been bothering me for a while. So in the updated version, the number-calling phase will involve pointing at the opponent’s target cards one by one, as you guess both their position and value.

We’re also changing the card stand itself. The simple stand included in the TRiNiTY Standard Edition tips over easily and is difficult to use. On the other hand, the wooden stand in the High-Grade Edition is bulky and heavy—making it impractical to carry around. That’s why the second edition will feature a more compact and user-friendly stand. We plan to package the three main components—cards, stand, and a dedicated memo pad—into a neatly sized box for better portability and usability. We’ll also be making small adjustments to the card design and upgrading the package logo with foil stamping to give everything a cooler, more stylish look. Plus, I’m working with my cousin, who’s an English teacher, to include an English rulebook and a lore booklet in the new version.

I’m developing the second edition to be easier to play, better-looking, and able to reach even more people than before.

Dragon Create
桃居土 竜（Ryo Momoido）