The creator says Claude Opus 5.5, run through Claude Code, built the game from an empty Unity project in a single session lasting 36 hours and 45 minutes.
The Windows build is a 1.7 GB ZIP file. The post instructs users to unpack it and run WorldOfOldcraft.exe, and reports about 72 FPS in the city at 1440p on an RTX 3060 laptop. A separate 1.3 GB report archive contains three pages: the agent brief, a chronological build record with gameplay recordings and timelapses, and figures for time, tokens, Higgsfield credits, and costs.
The 50 MB build kit includes TASK.md, CLAUDE.md, hooks, skills, approved concepts, and an installer intended for an empty Unity project. The installer downloads Mixamo animations and reference images. No keys are included: reproducing the build requires a fal.ai key and a Higgsfield account, with further prerequisites listed in the README.
The post does not independently establish the game’s code quality, the repeatability of the result, or the reported performance, token, credit, and cost figures.