This is how you start small with AI game development [AI Game Development Log #5]

You are a legend. Thank you for opening this article again today.

In my previous article, I wrote about how the "order" of steps is more important than "talent" when it comes to making games.

Back numbers↓↓↓

#1

#2

#3

#4

First, envision the game you want to make. Next, shape it into a playable state. After that, add the visuals and the feel. This time, I would like to write about that process using an actual example.

The first thing to do is to tell the AI.

When you hear "making a game using AI," you might feel like you are doing something special. But what you are actually doing is surprisingly simple.

When I actually make a game, the first thing I do is just one thing: tell the AI "what kind of game I want to make." This time, I will write about that flow using the Tissue Character Test game as an example.

That said, there is one thing I want to tell you honestly. I don't really remember the detailed steps I took when I made the Tissue Character Test game anymore. But there is one thing I remember clearly. That is, "I didn't try to make the whole thing from the start."

What I aimed for first was not the finished version. First, I made it so that I could "write characters on a tissue," and that was all.

I started by making just the foundation

When I actually made the Tissue Character Test game for the first time, I was using ChatGPT. However, this time, to show you that flow in an easy-to-understand way, I will proceed using Gemini 3.1 Pro.

First of all, I asked Gemini 3.1 Pro like this.

That is all. It is quite rough. But at the beginning, this much is enough. At this stage, there is no need to decide on all the detailed rules or effects. First, it is to see if the foundation of the game works.

Then, in less than a minute, Gemini returned the code that would serve as the foundation for the game.

That said, just having the code displayed doesn't make it a game. To actually play it, you first need to paste this code into an editor, save it, and open it in a browser.

This time, I will use an editor called VS Code to paste the code.

Once you have pasted the code into VS Code, save it as index.html inside a folder you have prepared in advance.

Now, by clicking on index.html, you can run the Tissue Character Test game.

Now, let's check how the game actually works.

It turned out to be a game where you can freely write characters on a white canvas themed like a tissue. Every time you write, a score is added. First, such a simple foundation was created.

However, this just ends with being able to "write." So, next, I decided to add rules. I asked Gemini for the following:

Gemini immediately corrected the code. When I actually ran it, a prompt was displayed, and as I wrote according to it, points were added, and I could proceed to the next prompt once I finished writing. Furthermore, that tension of the tissue tearing with a rip if you wrote too hard was also added.

The initial foundation of "just being able to write" has now become a playable game where you "take on prompts and write without tearing the tissue." All I did was ask roughly, run it, and add what was missing.

If an editor is too difficult, you can also build it with Gemini Canvas

The example above explained how to run a game by pasting the code created in Gemini into an editor called VS Code, but some people might find installing VS Code confusing.

In that case, I would like you to try building a game using Gemini's Canvas feature.

First, please access Gemini. Then, select the Canvas feature in Gemini and choose Gemini 3.1 Pro.

For example, let's say you want to create a side-scrolling shooting game where you defeat aliens with a spaceship.

I select the Gemini Canvas feature, choose 3.1 Pro, and enter the prompt: 'I want to make a side-scrolling shooting game where you defeat aliens in a spaceship.'

Then, it starts creating the game.

Here is the completed game↓↓↓

From there, if you ask Gemini to increase the types of enemies, you can add variety to them.

Also, if you ask Gemini to introduce items that power up your ship, power-up items will appear.

Furthermore, the Gemini Canvas feature is also effective for creating educational games for children.

Game development can be done by adding features one by one.

In this way, AI game development can proceed through small additions.

Step 1
First, roughly decide what kind of game you want to make.

Step 2
Instruct the AI on what kind of game you want to create.

Step 3
Try running it.

Step 4
If you feel something is missing, add rules little by little.

Following this flow, you can gradually shape your game.

You don't need to try to make a perfect game from the start.

First, try making something that works.

Then, add a little bit of "fun" to it, step by step.

Ultimately, this is the process I follow whenever I build games with AI.

Building games has changed my life a little

Being able to build games like this has changed my life a little.

Before that, my days were like this: just commuting between home and work, exhausted, with no hopes or dreams, feeling completely drained. I wasn't particularly good at my job, and I lacked self-confidence. I didn't have any real hobbies, and my days off were spent cooped up at home, watching YouTube until the day was over.

Every day was a repetition of the same thing, and I would vaguely wonder, "Is this all there is?" When I looked at social media, people who were creating things seemed so brilliant. I didn't have any special talents. I wanted to start something new, but time just kept passing by without me doing anything.

However, things started to change little by little after I began building games with AI. People started playing the games I made, and I began receiving more feedback, with people telling me they were "amazing" or "fun." Thanks to that, building games became a hobby, and it gave me a new vitality for life. I was also happy to make new connections on social media.

Of course, my life didn't change completely overnight. But having one thing that I could "create" for myself was a huge deal.

I want you to try making one, even just once

That is why I feel this way.

For those who want to start something new but can't find a starting point, those who feel a bit unfulfilled by the daily commute between work and home, or those who love games but have never been on the "creator" side—I want you to try building a game, even if it's just once.

And if possible, I would be happy if this reached a wider audience as well. I want to tell children who are struggling with school or studies and spending a lot of time at home, as well as parents who are worried about their children, that the experience of building a game yourself, playing it, and having others play it is more fun and moving than you might think.

Building a game might sound like a big deal. But at first, it can be really small. Text appearing on the screen. Moving when you press a button. The score increasing. Even just that, the experience of seeing something you made yourself move is quite a joyful one.

I know you might feel anxious about starting alone

However, some of you reading this far might have thought, "I understand the concept, but can I really do it all by myself?"

I was the same way at first. If you ask AI, it will give you code. But what should you ask? Where should you start? What should you do if an error occurs? There are times when you get stuck on those parts.

That is why, this time, I have compiled this process into "a certain format" so that anyone can build a game in the same way.

I will reveal what that is in the next post, #6.

See you in #6!

Thank you for reading until the end!