One-Shotting a Raccoon Heist Game with Claude Fable 5

In 2026, Simon Willison attempted to have Claude Fable 5, running in Claude Code for web, build a complete game from a 2022 tweet that contained GPT-3-generated text and DALL-E images about a raccoon heist game. He gave Claude a prompt with the images and instructions to work independently, commit often to a GitHub Pages branch for previewing, and use an OpenAI API key for image generation. Claude built a 3D browser game using Three.js, generated textures with gpt-image-2, and conducted automated tests with Playwright to fix bugs like the raccoon being invisible on mobile. The game features gameplay mechanics such as collecting loot, avoiding a patrol dog with scent tracking, and a police cruiser, all while managing a time limit. The project was completed in 7 commits, with all assets generated procedurally or via API, and the final game is playable at the link provided. Willison notes the game is an impressive proof of concept but not particularly fun, yet highlights the potential of such autonomous AI development.