Fable Cities
Free · play online in your browser, no download
A 3D city builder in a browser tab, still in development, written by a team of Claude Code agents from a single published prompt.
Official site fablecities.rawscollections.com, verified Nov 3, 2026. Linked as “Play it now” from the developer's own GitHub repository README (rawprogress/fable-cities).
Where to play
Every platform this game is on. Links are checked against official sources; we never host or mirror games.
- Play free — official siteBrowserReleased · In development (README status badge); playableFree
Runs in a desktop browser. No download.
Browser (no download) · Official link verified Nov 3, 2026.
- View on GitHubGitHubReleased · Source, README, prompt and licence (MIT for code, CC0 assets); the README still says everything ships when the game is finishedFree
Source code repository, not a place to play.
Official link verified Nov 3, 2026.
About Fable Cities
Fable Cities is a free real-time 3D city builder that runs in the browser with Three.js and WebGL2, still marked as in development. Start a new city on land generated from your own seed, or load a grown demo city of about 20,000 people. You draw roads (local roads, avenues, highways and paths) on a heightmap landscape with rivers, coastline and cliffs, zone cells along the road frontage for residential, commercial, office and industrial buildings, and let the clock run: buildings go up across five levels, traffic drives a lane graph with car-following and yielding at junctions, and the simulation tracks the economy, population and jobs, demand, happiness and service coverage. Day and night, the sun's path through the year, rain, fog and snow are simulated, and the whole soundscape is synthesised at runtime. A desktop is recommended, and the first load pulls about 160 MB of textures. The developer, who goes by raw, says every line of code was written by AI agents from one instruction handed to Claude Code once: builder agents own one folder each, and separate critic agents screenshot and score their work against reference images until it passes. The README is open about the result: the game is playable but has not met its own visual bar, there is no in-game tutorial, and a fresh city takes a couple of minutes before anything visibly grows. In English.
How it was built
Partially verifiedThe README says: “Every line of code here was written by AI agents. The instruction they ran on is in PROMPT.md”, and carries a “built with Claude Code” badge; PROMPT.md says the instruction was handed to Claude Code once and the model did the rest. The prompt asks for an architecture document first, a headless-Chrome screenshot tool before any features, one builder agent per module working in dependency waves with one integrator agent, a separate critic agent (who writes no code) scoring each module 0–10 against reference screenshots with 8.5 as the pass mark, blind A/B judging at the end, and a loop until every critic passes.
- DeveloperPROMPT.md: “It is handed to Claude Code once, and the model does the rest”; the full instruction is published with notes on why each step is there. — GitHub (rawprogress)
One prompt, then a team of agents, per the README: the model wrote ARCHITECTURE.md (folder ownership, shared world model, module APIs, units, determinism, performance budget) before any feature, then builder agents each owned one module folder while critic agents took their own screenshots at several times of day, checked console errors and draw calls, and sent back ranked defect lists below the pass mark; scores and open defects are kept in docs/STATUS.json so each loop resumes at the weakest module. A headless Chrome harness on a real GPU writes a screenshot and log before an agent may report a feature as working. Rendering uses cascaded shadow maps, ambient occlusion, bloom, SMAA and filmic tone mapping; assets are CC0 only. The README reports that three rounds of blind comparison against a commercial city builder were lost 0–4 each, with the gap narrowing from 3.4 to 2.5 points.
- Engine / framework
- Three.js
- Languages
- JavaScript
- Team size
- Not disclosed
- Development time
- Not disclosed
- Development cost
- Not disclosed
- AI-written code
- ~100% of shipped codeDeveloper ReportedGitHub
“Every line of code here was written by AI agents. The instruction they ran on is in PROMPT.md.”Verification notes: Features, method, current state and the AI statement come from the repository README and PROMPT.md, read through raw.githubusercontent.com on 6 Nov 2026; LICENSE reads “Copyright (c) 2026 raw (github.com/rawprogress)”. The developer is pseudonymous (“Built in public by raw”, X @raw_dev_x) and writes the prompt in the first person; no real name or location is given. The README describes Cities: Skylines II as the visual benchmark the critic agents scored against and its disclaimer says no code, art, audio or assets from that game are used and the project is not affiliated with Colossal Order or Paradox Interactive; the comparison is the developer's. The game page loaded on 6 Nov 2026; its scripts make no calls to AI services. The README says everything ships at once when the game is finished, but on 6 Nov 2026 the repository already held the source (package.json, index.html, src/main.js, src/modules/, tools/, ARCHITECTURE.md, docs/STATUS.json), read through raw.githubusercontent.com. No release date is given and repository dates and stars were not checked (the GitHub API was not reachable from our checker). The game was not played.
Game performance
Each figure measures something different — concurrent players, owners, downloads and sales are never interchangeable and are never added together. Labels show where each number comes from.
Browser (official site)
Free in the browser. Desktop recommended; the first load downloads about 160 MB of textures.
No public metrics recorded for this listing.
Not publicly available: Concurrent players (site), Monthly revenue, Gross revenue.
GitHub
No public metrics recorded for this listing.
Not publicly available: GitHub stars.
Sales & revenue (all platforms)
Browser game — there are no downloads to count.
Reviews & rankings
Not yet reviewed by our editors.
Not currently ranked.
Sources
| Source | Type | Published | Accessed |
|---|---|---|---|
| rawprogress/fable-cities (README, LICENSE) GitHub | Repository | Not confirmed | Nov 3, 2026 |
| The Prompt (PROMPT.md) GitHub (rawprogress) | Repository | Not confirmed | Nov 3, 2026 |
| Fable Cities (game page) rawscollections.com | Official site | Not confirmed | Nov 3, 2026 |
| Official game page (language check) raw | Official site | Not confirmed | Nov 3, 2026 |
