The basics
What is Universal Modder?
A free, MIT-licensed toolkit (GitHub: rehan-remade/universal-modder) that lets AI coding agents mod PC games you own: 11 Agent Skills, the um CLI, a fal MCP server for generated assets, and a shared knowledge base of field notes.
Who made Universal Modder?
Rehan (@rehan-remade on GitHub, @rehan_shei on X), who packaged what Claude Code learned modding Terraria and Age of Empires II. Community agents and humans have since contributed dozens of field notes.
Is it a mod generator?
No. It doesn't produce mods by itself. It gives an agent a method and tools; the agent does the work with you approving risky steps.
Is universal-modder.dev official?
No. It's an independent guide. Install only from the GitHub repo.
Install and setup
Which AI agents does it support?
Claude Code, Codex, Gemini CLI, VS Code with Copilot, Cursor and OpenCode have install routes; anything else can clone the repo or use npx skills add. Install guide.
What do I need installed?
Git, Python 3.10+, ffmpeg, and ideally uv. Blender only for 3D-to-sprite renders. A fal key for generated assets.
Does it work on Mac or Linux?
Setup, knowledge base, asset tools, backups and publish checks: yes. Driving and recording the game (um win) is Windows or WSL only.
How do I use it with Claude Code?
Run /plugin marketplace add rehan-remade/universal-modder then /plugin install universal-modder@universal-modder, set FAL_KEY, and ask for a mod. Full walkthrough.
Cost
Is Universal Modder free?
The toolkit is free. Your agent plan and fal assets are separate. Cost breakdown.
How much does a mod cost in fal credits?
Code-only mods: $0. A small content pack (10 high-quality sprites, a key-art image, a 3D model, 10 seconds of SFX) is about $2.51 at current prices.
Games
Which games has it modded?
42 games have field notes, including Minecraft, GTA V, Terraria, Age of Empires II, Baldur's Gate 3, Elden Ring and Risk of Rain 2. Game library.
Can it mod Palworld?
There's no Palworld field note yet. It's an Unreal Engine 5 game, so the Unreal playbook's UE4SS and pak routes apply. Palworld page.
Can it mod online games?
Not online games with anti-cheat. Single-player modes and servers you run are fine.
Safety
Will I get banned?
Not if you stay offline or on your own servers. It refuses anti-cheat bypasses and cheats against other players. Safety rules.
Can I publish what it makes?
Yes: your code, your assets and patches. Never the game's files or decompiled code. um publish check catches the obvious problems.
Comparisons
Is it the same as universal-game-modder?
No. That's an unrelated npm MCP server. Comparison.
Do I still need BepInEx, UE4SS or tModLoader?
Yes. Universal Modder builds on community loaders rather than replacing them. How they fit.