Rainbow Frontier

Rainbow Frontier is a js13kGames 2026 Online entry for the theme Unicorns and Rainbows.

Ride an animated unicorn through a continuously generated 3D frontier, cleanse Grey Growths, fight the Grey Beast, restore regions, meet other players, chat, use herd pings, and play Hoof & Cross on a physical board in the shared world.

Source layout

• index.html — readable development source and the authoritative game source.
• dev-relay.js — tiny local emulator for the js13k Online relay protocol; development only.
• PACK_RELEASE.bat — Windows release builder and 13,312-byte size gate.
• tools/build/build.mjs — folds the HTML/CSS shell into JavaScript, minifies with Terser, and packs with Roadroller.
• tools/build/maxzip.py — deterministic maximum-DEFLATE ZIP writer using Zopfli when installed.
• tools/build/package.json / package-lock.json — pinned JavaScript build dependencies.
• requirements.txt — Python packaging dependency used by the release build.

Generated files (node_modules, tools/build/dist, and release ZIPs) are deliberately not committed.

Controls

• WASD — ride
• SHIFT — gallop / charge
• SPACE — jump
• RMB — Rider Steer
• Mouse wheel — camera zoom
• ENTER — world chat
• F — Hoof & Cross interaction
• 1–4 — herd pings
• M — mute / unmute

Build

Requirements:

• Node.js + npm
• Python 3
• Python package zopfli==0.4.2

Install dependencies:

cd tools/build
npm ci
cd ../..
python -m pip install -r requirements.txt

On Windows, run:

PACK_RELEASE.bat

The builder:

1. syntax-checks the development JavaScript,
2. minifies it with Terser,
3. packs it with Roadroller using deterministic seed 7,
4. creates a self-contained index.html,
5. builds RainbowFrontier_release.zip, and
6. fails if the archive exceeds the js13kGames 13,312-byte limit.

The frozen release-candidate build is reproducible at 13,063 bytes, leaving 249 bytes under the limit when built with Zopfli.

Online mode

The production client uses the official js13kGames Online relay. dev-relay.js exists only for local multi-client development/testing and is not part of the submitted release ZIP.

The multiplayer model keeps gameplay state client-reconcilable: Growth cleansing, Grey Beast damage, region restoration, player movement/chat/pings, and Hoof & Cross are exchanged through compact relay messages without a custom production server.

Release archive

The actual js13kGames submission archive is intentionally not stored in this source repository. It is generated locally by PACK_RELEASE.bat and submitted separately.