AI Agents Used to Build Co-Op Versions of Single-Player Games, Including Fallout: New Vegas and Deus Ex

A developer who goes by cranebeaker has released Co-op Anything, a project that lets players configure an AI agent to turn any single-player game into a co-op game. The result can be played online or in split-screen mode.

The code quality of these mods may raise questions, but they work well enough.

AI has already produced a wide range of mods. Cranebeaker decided to build a tool for creating co-op mods specifically.

The project is designed for Claude Code, Codex, Gemini CLI, Cursor, OpenCode and other tools. The developer built in two main workflows. If a game already has a co-op mod, the AI agent tries to find the latest version and improve it. If no such project exists, the agent has to study the game’s source code or reverse-engineer the game, and then create a co-op mod:

Want to play a single-player game with your friends? Send your AI agent to this repository. It will study the available data, reverse-engineer the game and its engine if necessary, create or fix the co-op mode, test it with bots inside the game, and package the result so your friends can install it with one click and join through Steam.

According to cranebeaker, if a co-op mod already exists for a game but is buggy or abandoned, the AI agent will in most cases need several days to finish the job. If nothing exists at all, the difficulty depends on the game’s engine.

He also named several co-op mods that are either ready or in development: Deus Ex (deus-ex-coop), The Legend of Zelda: Ocarina of Time (ocarina-coop), Fallout: New Vegas (fnv-coop) and Dungeon Keeper (dungeon-keeper-coop).

AI agents are turning single-player games into co-op games, with work underway on co-op for Fallout: New Vegas, Deus Ex and more — Image source: Ion Storm, Eidos Interactive Corp.

Cranebeaker has published the source code for the “coop-anything” project on GitHub.

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