Claude Fable 5.2 is a frontier model from Anthropic that can work autonomously on long coding tasks. Given one detailed prompt, it can plan, write, test and refine a complete game over several hours of agentic work, with no human writing code in between. Every game in this arcade was produced that way.

Everything ships inside one .html file: markup, CSS, JavaScript, shaders, procedurally generated textures and synthesized audio. 3D games draw through WebGL (often with an inlined copy of Three.js), sound comes from the Web Audio API, and the levels, models and music are generated in code at runtime rather than loaded as separate assets. Open the file in any modern browser and it runs, offline, without a server or build step.

A one-shot prompt is a single instruction given to the model at the start: the design brief, constraints and acceptance criteria all in one message. The model then builds autonomously. Where the original or a faithful reproduction is available, open the “View Prompt” tab on any game to read and copy it.

Yes. Games we host are served from a sandboxed endpoint with a Content-Security-Policy sandbox and an iframe sandbox that allow scripts and pointer lock only, so game code cannot read this site’s cookies or storage, open pop-ups, or navigate the page. Games marked “Author-hosted” are embedded from the creator’s own website in a sandboxed iframe on their own origin, which keeps them isolated from this site too.

Every game has a “Download .html” button and a source inspector. Because each one is a single file, you can open it in any editor, change it and run it locally straight away. Please respect the original author’s license and give credit when you share a remix.

Use the Submit page: upload your .html file (up to 10 MB), add the prompt and controls, and link to your post. No account is needed. Submissions go live after a quick review.