A little leap of adventure.
A one-shot prompt game built with GPT-6 Astra in GitHub Copilot CLI.
Three worlds. Nine sun shards. One very determined little sprout.
Play now | The prompt | Controls | Worlds | Run locally | Contribute
An original browser game, not a video or a mockup. Everything pictured is playable.
- Open SkySprout.
- Press Enter or click Let's play.
- Use Left / Right to move, Space to jump, and Shift to run.
No install. No account. No API key. No model subscription needed to play.
SkySprout is a small, complete pixel platformer. Guide a leaf-topped explorer through a sunny meadow, a glowing grotto, and a cloudtop canopy. Collect coins, bounce on beetles, find sunfruit shields, and light the lantern at the end of each world.
| Feature | What you get |
|---|---|
| Three complete worlds | Original layouts, colors, scenery, and increasingly tricky jumps |
| Nine sun shards | Three optional collectibles in each world |
| Responsive movement | Walking, running, variable-height jumps, coyote time, and buffered jumps |
| Enemies and power-ups | Stompable beetles, hopping enemies, breakable bricks, and one-hit sunfruit shields |
| Checkpoints and lives | Mid-world respawns and an extra life for every 50 coins |
| Original pixel art and sound | Code-drawn sprites, parallax scenery, particles, and synthesized music and effects |
| Keyboard and touch | Keyboard shortcuts on desktop and on-screen buttons on touch devices |
| Browser-local best score | Your personal best and sound preference stay in your browser |
SkySprout started with one creative prompt on September 8, 2026, using
GPT-6 Astra (gpt-6-astra) in GitHub Copilot CLI.
The original prompt, as typed:
not using any skills and just only the model, build a super mario orignal nintendo game that i can play on my keyboard
The result was an original game, SkySprout, rather than a reproduction of Nintendo's game. Its characters, sprites, level layouts, scenery, and audio were created for this project.
| Build ingredient | What was used |
|---|---|
| Model | GPT-6 Astra |
| Coding environment | GitHub Copilot CLI |
| Creative brief | The one initial game-building prompt above |
| Skills | None |
| Subagents or multi-agent orchestration | None |
| Game framework or starter template | None |
| Downloaded artwork, music, or ROMs | None |
| Runtime | HTML, CSS, JavaScript, Canvas 2D, and Web Audio |
| Runtime dependencies | None |
What "one-shot" means here: one initial creative brief, followed by autonomous implementation and refinement in the same build session. The model used file, terminal, and browser tools, ran checks, and corrected issues. It does not mean one model response or an untested first draft. Repository documentation, automation, and public publishing were requested afterward.
The game does not call a model while you play. The AI was used to build it, not to run it.
| Action | Keys |
|---|---|
| Start / continue | Enter |
| Move | Left / Right arrows or A / D |
| Jump | Space, Up arrow, W, or Z |
| Run | Shift or X |
| Pause / resume | P or Escape |
| Toggle sound | M |
| Restart the entire adventure | R |
A few things worth knowing:
- Hold jump for a higher leap. Use Shift + Space for the wider gaps.
- Land on enemies from above; touching their sides hurts.
- Hit leaf-marked blocks from underneath to find coins or sunfruit.
- A sunfruit shield absorbs one hit and lets you break brick blocks.
- The small pennant marks a checkpoint. The tall sky lantern finishes a world.
- Sun shards are optional. You can finish without collecting all nine.
Switching tabs or leaving the game window pauses the adventure. Sound begins only after you interact with the page.
| World | The adventure |
|---|---|
| 01 - Sunlit Meadow | Learn the rhythm among sunny hills, stone pillars, and friendly-looking trouble. |
| 02 - Glowstone Grotto | Follow the crystals through a darker world of ledges and hopping enemies. |
| 03 - Cloudtop Canopy | Take on wider gaps and a final climb toward the last sky lantern. |
Glowstone Grotto. Follow the glow. Mind the gaps. |
Cloudtop Canopy. One last climb. The whole sky is waiting. |
No developer tools required: download the ZIP,
unzip it, and open index.html in a modern browser. Keep engine.js, game.js,
and style.css beside it. This local copy works entirely offline.
Or clone the repository:
git clone https://github.com/DUBSOpenHub/skysprout.git
cd skysproutThen open index.html. There is no package installation or build step.
| File | Purpose |
|---|---|
index.html |
Game screen, menus, controls, and accessible labels |
style.css |
Responsive arcade layout and touch controls |
engine.js |
Fixed-step physics, collisions, worlds, enemies, collectibles, and game state |
game.js |
Canvas rendering, original sprites, keyboard/touch input, sound, and local score storage |
tests/engine.test.cjs |
Physics, state transitions, jump-window checks, and complete input-driven playthroughs |
.github/workflows/ci.yml |
Checks every change and publishes the playable site from main |
.github/workflows/codeql.yml |
Scans JavaScript and GitHub Actions on pushes, pull requests, and a weekly schedule |
The engine is independent of the browser so gameplay can be tested with Node's built-in test runner. The browser runs it at a fixed 60 simulation steps per second and draws the game on a 480-by-270 canvas.
Use Node.js 22 or newer:
npm run check
npm testNo npm install is needed. Tests cover movement, jumps, collisions, shields,
collectibles, checkpoints, pausing, game over, and world completion. Recorded
keyboard-input playthroughs also finish every world and collect all nine sun
shards without teleporting or losing a life.
The deployment workflow publishes only the four game files, not the tests, repository documents, or screenshots. Forks can run the same checks; publishing their own site requires enabling GitHub Pages with GitHub Actions as the source.
Do I need GPT-6 Astra or GitHub Copilot to play?
No. Open the game in a browser. There are no runtime AI calls.
Does it save my place?
Your personal best and sound setting are saved when browser storage is available. The current run is not saved across page reloads. Checkpoints apply within a run.
Does it work offline?
The downloaded local copy does. The hosted site needs a connection to load its files; it does not install an offline cache.
Does it collect data?
The game contains no analytics, tracking, account system, or backend. Best scores and sound preferences are browser-local. The public website is hosted on GitHub Pages; local play does not need hosting.
Is this an official Nintendo game or a remake?
No. The prompt used a familiar game as a reference, but SkySprout contains no Nintendo code, characters, sprites, music, level maps, or ROMs, and is not affiliated with Nintendo.
Found a tricky corner, want to add a world, or have an accessibility improvement? Read CONTRIBUTING.md and AGENTS.md, then open an issue or a pull request. Keep the game original, dependency-free, and easy to run.
Report vulnerabilities privately using the process in SECURITY.md.
MIT - use it, fork it, build on it.
Created by @DUBSOpenHub with GitHub Copilot CLI, powered by GPT-6 Astra.
One creative prompt. An original little adventure.