Universal Modder: Claude makes mods for almost any PC game
- GitHub stars
- 5.3K
- engine playbooks
- 12
- open source
- MIT
You want a new weapon in your favorite game, a new civilization, or Minecraft running inside GTA V. Universal Modder teaches Claude Code to mod almost any PC game you own: it finds the engine, reads the game's real code, builds the mod, makes the art and tests it in the running game.
What it is
A set of skills, tools and a shared knowledge base for agents like Claude Code. The agent finds the game, works out the engine and the modding route, reads the real code, builds the mod, makes art, 3D and sound through fal, tests the mod in the running game and cuts a video. Open source, MIT.
It ships 12 ready playbooks for different engines: Unity, Unreal, Godot, Source, Bethesda engines, Minecraft, Age of Empires II, native C++ and more.
After each mod, the agent writes a note to the shared knowledge base: which versions worked and where the traps were. The next agent starts from there, not from zero.
Examples in the repo: a homing rocket launcher and a nuke for Terraria, a new civilization for Age of Empires II, and real Minecraft inside the GTA V story mode.
Steps
Step 1. Open Claude Code
Open it on the computer where the game is installed. Windows games work directly or from WSL.
Step 2. Paste the prompt and name the game
Claude installs the plugin, checks what's missing and backs up your saves before it changes anything.
Step 3. Describe the mod in plain words
For example: add a homing rocket launcher to Terraria. Claude reads the game's code, builds the mod, tests it in the game and asks before it takes over your mouse and keyboard.
Copy this into Claude Code
Install the universal-modder plugin from github.com/rehan-remade/universal-modder for Claude Code and check that it works. Check whether I have Git, Python 3.10 or newer and ffmpeg, and install whatever is missing. Ask me for a fal key only when you need it for art. Then find my game [game name], work out its engine and modding route, and back up my saves. The mod I want: [describe the mod in plain words]. Explain what you're doing in simple words, and ask before you take over my mouse and keyboard or put a mod loader into the game folder. If something doesn't install, explain what the problem is and fix it. I'm not a programmer: anything you can do yourself, do it yourself.
Want this working for your business?
- AI agents for your business
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Good to know
Knowledge base first
Before it starts, the agent searches the knowledge base for notes on your game. If someone has modded it before, it starts from the known route and the known traps.
Art through fal or locally
The agent makes sprites, textures, 3D, sounds and music through fal with a key. Images also work without a key through a local ComfyUI server. Turning 3D into sprites needs Blender.
Your saves are safe
Before it touches your saves, the agent copies them, and it only closes processes by their exact ID so nothing else gets hit.
The honest read
- Only games you own: single-player, multiplayer and servers you run yourself. It stays out of online games with anti-cheat, won't write cheats against other players, and won't get around anti-cheat, DRM or ownership checks. Follow the game's own rules too.
- Game files and decompiled code never go into the mod. A mod is code, your own assets, patches or converters.
- Art through fal only works with a fal key. Without one, you still get images through a local ComfyUI.
- The project is young: it appeared on September 30, 2026.
Want this built for your business?
I build AI agents and automations for businesses, and do 1:1 consulting calls. Message me on Instagram with what your business does, and I'll tell you what can be automated.
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