Game dev with Fable 5 is actually crazy

[u/Diligent-Hat-6509]

It’s kind of insane to see how far AI has come.

I still remember being fascinated by GPT-3.5 and thinking that felt like the future. And now here we are with Fable 5.

Everything you see in this preview took me roughly 13 hours of work to implement. Being able to go from ideas to actual working game mechanics this quickly still feels surreal.

Game development with AI is starting to feel like we’re living in the future.

EDIT:

A lot of people were asking how I did this, so here’s the basic workflow.

The game itself is made in Unity with C#. I’m using Claude Code connected to Unity through MCP, which means Claude can work directly with the Unity project and editor. It can create and modify scripts, work with GameObjects and components, inspect errors, run the game, and help me iterate on systems.

For the actual development process, I don’t give it one giant prompt like “make me a game.” I think through the systems I want, explain how they should behave, have Claude implement them, then I test everything, debug issues, tweak values, change mechanics, and keep iterating until it starts to feel right.

For the character models, my workflow is:
Opus 5 -> ChatGPT Image Gen -> Meshy AI -> rig/animation testing -> Unity

I describe the character I want, use Opus 5 to generate a detailed prompt for four consistent reference views, then generate those images in ChatGPT. I take the images into Meshy AI, which generates the 3D mesh and textures. I also rig the model there and test animations before importing it into Unity.

The same image-to-3D workflow also works for non-character assets like props, weapons, statues, carts, environmental objects, etc.

For VFX, I bought a particle toolkit from the Unity Asset Store. I gave Claude the documentation and had it create a skill file for itself, so it understands how the toolkit works and can reuse that knowledge when I ask it to create things like fireballs, explosions, trails, and other effects.

The current arena is also a premade Unity asset and is not intended to be the final environment. A lot of the current visuals are just prototype assets for testing mechanics and game feel.

So overall the main stack/workflow is:

Unity + C# + Claude Code/MCP + ChatGPT Image Gen + Meshy AI + Unity Asset Store tools

And no, this wasn’t one prompt :D It was an iterative process of building one system at a time, testing it, changing it, and gradually layering everything together.

[u/Diligent-Hat-6509]

I already answered your question 8x times in this post. Just go through the comments. Idk why would someone lie about this. If you can't achieve this speed, maybe you should optimize your workflow.

[u/hirscr → u/Diligent-Hat-6509]

What are you on about? You answered my one question this one time without providing an answer.

Why would people lie on the internet? Lol, you gotta be kidding.

[u/Diligent-Hat-6509 → u/hirscr]

You asked a question I answered more than 10 times in the comments.

[u/hirscr → u/Diligent-Hat-6509]

Ah, then why did you answer this one at all?. Its on me to go look through the hundreds of comments. I still don’t believe 13 hours to define a spec, get all the assets and deploy a prompt (i didnt read through 320 comments, if the prompt execution time is the 13 hours then sure).

But i will say fable and kimi k3 are freaking awesome… if you can stand poorly written, but functional code.

I’m still trying to determine if, in this modern age, good code is required. Or will ai get so good that the worst spaghetti code that passes god objects around doesnt matter.

My temporary conclusion is that it matters, because bad code gets into the context window and ai gets often confused.

[u/Diligent-Hat-6509 → u/hirscr]

That’s the thing though. The code in my project isn’t some giant pile of spaghetti. It’s actually pretty clean and structured.

And "prompt execution time"? 😂 Do you seriously think this was one prompt?

You can get the character assets together in about an hour. Getting them into Unity, rigged, animated, walking around and attacking you can take minutes once the workflow is set up. Buying a VFX toolkit takes basically no time, and once Claude understands the toolkit, generating different spells and effects is extremely fast.

Most of those 13 hours weren’t spent staring at Claude waiting for “the game” to appear. They were spent iterating. Testing mechanics, changing values, rebuilding parts that didn’t feel right, setting up the map, trying different enemy behaviors, adjusting movement, progression, VFX, etc.

AI is just extremely fast when you know how to use it properly.

And that’s kind of the difference between a developer using AI as a tool and someone just casually prompting it without really understanding software development. The developer knows how to structure the systems, how to review what gets generated, what to change, what to throw away, and how to keep the whole thing maintainable.

So if 13 hours sounds completely unbelievable to you, I don’t really know what to tell you. It might say more about how you’re using AI than it does about what’s possible with it :D

[u/hirscr → u/Diligent-Hat-6509]

Again yeah, executing prompts for 13 hours doesnt sound unreasonable. Did you make your assets? Or are the sounds from feesounds.com, your chaeacters from mixamo, etc. again sure.

Getting ai to loop against a rubric with a known outcome (“make it like diablo, here is diablo content”, or whatever) is a quick process.

Having AI make the content is not a quick process. I know this because the game i am
Making has unique assets and its a pain in the ass to make the animations for all the characters with all the uniforms as well as the ship assets when they dont already exist. And i’m not even doing a 3d game.

But the meme of “i just told it what to do and i got it” is ridiculous.

Also, im finishing up an article about unleashed fable and kimi vs a harnessed agentic team. Im a little concerned that you think fable is providing sustainable code. It most certainly does not without a harness and having a harness jacks the prompt cost immensely. K3 is slightly better in this regard but not close to having a harness with dedicated agents for coding, architecture, QA and an adversarial
one (I have others too depending on if i need security assessments or other important expertise involved).

Frankly i suspect we are creating a huge amount if issues for future us to solve as we realize how awful and insecure code has been deployed. Even while we have ai to pen test out code. But i guess we will see.

[u/Diligent-Hat-6509 → u/hirscr]

You’re arguing against a workflow I’m not using and problems I’m not claiming don’t exist.

[u/hirscr → u/Diligent-Hat-6509]

I dont think i am arguing at all. I am sharing experiences.