Magnitude Run

Endless runner for the Seismic community. Rocky, a stone golem with a Seismic crystal in his chest, runs along a seismograph trace through the city: Bank District, The Exchange, Glass City and The Enclave. Every jump is written to the trace behind him, and the score is a Richter-style magnitude from M 1.0 upward.

Fan-made. Not an official Seismic product.

Play

• Space / tap: jump. Hold for height, release early for a short hop.
• Down / swipe down / left touch zone: slide on the ground, dive in the air (a dive lands straight into a slide).
• Space in the air: stomp. The shockwave shatters Watchers, Probes, Rocks and glass within reach. Close to the ground it buffers a jump instead.
• Three cracks and Rocky shatters. Falling into a fault line costs a crack and puts you back on the far edge.
• Esc / P pause, M mute, Enter / R run again.

Hazards

hazard	from	answer
Glass Golem, Glass Spire	ground	jump (spire needs a held jump)
fault line (gap)	below	jump
Watcher, low	air	jump, or stomp it
Watcher, high	air	run under
Watcher beam, chest	air	slide
Watcher beam, shin	air	jump
Fangs	ceiling	slide
Glass Moth	air, flying at you	slide
Probe	above, dives at a marked spot	jump the stuck spike, or stomp it
Burrower	below, cracks then erupts	jump
Rock (rockfall event)	above, lands on a marked spot	jump the rubble
Vent	below	ride it up to the shard arcs

Aftershocks every 600 m step the speed up and, from zone 2, start an event: Tremor, Watcher swarm, Rockfall, Glass storm. Biomes change every two zones.

Power-ups

Shielded (one hit absorbed), Resonance (shard magnet, 10 s), Overclock (4.5 s invulnerable dash, fault lines are bridged), Amplifier (shards count double, 12 s), Repair (heals a crack; only offered when cracked).

Scoring

M = 1 + 2.2 · log10(1 + (metres + 20 · shards) / 50), capped at 9.9, with USGS classes. Shard chains build a multiplier (×2 at 5, ×3 at 10, ×4 at 15; 3 s timer; a crack resets it). Passing a hazard within 18 px is a close call worth 2 shards. Stomping several things at once is a combo.

Modes

• Endless: your best distance shows as a marker in the world.
• Daily: the same course for everyone, seeded from the UTC date. Its own leaderboard, kept for three days.

Missions (three at a time, from a pool of 43) raise your rank from Magnitude 1.0 to 9.0 and unlock skins (Obsidian, Rose Quartz, Glass, Enclave).

Runner name and save

The first visit asks for a runner name. The name is the player's row on both leaderboards and the key to their save on the server (rank, missions, skins, best runs), so entering the same name on another phone or browser brings the progress back. If a name already has a save, the game shows it and asks "is this you?" before loading it. There is no password: a save can only grow (counters merge by maximum, finished missions by union), so playing under someone else's name can add to their progress but never erase it.

The first Run opens a How to play guide (controls for phone and keyboard, every hazard and pick-up drawn with the game's own art, zones, modes, missions); the title has a How to play button for later.

Run locally

Static files, no build step. The local server also runs the leaderboard API against an in-memory store, so the whole online flow works without Vercel:

node serve.mjs 5173

Then open http://127.0.0.1:5173/. Handy URL flags: ?start=1200 begins an endless run 1200 m in (practice; not posted), ?nopause=1 keeps running when the tab loses focus, ?pwa=1 enables the service worker on localhost.

Deploy on Vercel

1. Import the repository in Vercel (framework preset: Other, no build command, output directory .).
2. Storage → Marketplace → Upstash Redis, attach it to the project. It sets UPSTASH_REDIS_REST_URL / UPSTASH_REDIS_REST_TOKEN (the KV_REST_API_* names also work).
3. Add an environment variable RUN_SECRET with a long random string (openssl rand -hex 32). Without it the Redis token is used as the signing secret, which works but is weaker.
4. Deploy. Without Redis the game still runs; the leaderboard just says it is offline and everything stays in the browser.

Hosting the static files elsewhere (GitHub Pages) while the API lives on Vercel also works: set window.MR_API_BASE = 'https://your-app.vercel.app' before src/main.js loads.

API

endpoint	purpose
POST /api/start	issues a signed run token that carries the start time
POST /api/submit	validates a run (token, single use, elapsed time vs distance, zone and magnitude recomputed, shard plausibility, rate limits) and stores the best per runner name
GET /api/board?board=global|daily&limit=25&name=	top list plus the runner's own rank
GET /api/profile?name= / POST /api/profile	a runner's save: read it, or merge this device's save into it

A runner is their name (case-insensitive), never an account. Names are 2 to 14 characters, filtered server-side; "Rocky" is reserved. This is honest-player anti-cheat: the input-log replay verification in the roadmap is what would make it strict.

Files

file	what
index.html, styles.css	shell, title, result, leaderboard, missions and settings panels
src/game.js	loop, physics, spawner, events, collisions, HUD
src/hazards.js	hazard registry (update/draw/hit per type), patterns, events, power-ups
src/rocky.js	Rocky, Shard, Watchers and Glass Golems as procedural vectors; poses; skins
src/world.js	the four city districts (parallax layers, baked to bitmaps on phones)
src/input.js	keyboard, mouse, touch zones and swipe → jump / down
src/audio.js, src/music.js	WebAudio cues and the adaptive procedural score
src/missions.js	missions, lifetime stats, ranks, skin unlocks
src/net.js	leaderboard and profile client
src/save.js	the runner save and its merge, shared by the browser and api/profile.js
src/howto.js	How to play illustrations, drawn with the hazards' own art
src/card.js	1200×630 share card
src/ui.js, src/main.js	DOM panels and wiring
api/	Vercel functions (_lib is shared code, not a function)
design/	Rocky character brief and turnaround for designers
sw.js, manifest.webmanifest	installable, offline-capable shell
favicon.ico, favicon-*.png, icon-*.png, maskable-512.png	the logo at every size, drawn by design/logo.html from the in-game Rocky

Roadmap

• Replay-verified leaderboard: record inputs, re-simulate on the server with a deterministic fixed-step core.
• More hazards from the design notes: Shard Teeth, Glass Bomb, Cipher Gate, Mirror Watcher bait, armoured Golems.
• Ghost of your best daily run, weekly board, friend markers.
• Rocky sprite art from the design brief in design/CHARACTER.md.

Brand

Palette and type follow the Seismic Brand Kit v2: Mauve #825A6D, Purple #523542, greys from #FCFCFC to #161616. Suisse Intl and Suisse Works are licensed faces, so the web build uses Instrument Sans and Instrument Serif as free stand-ins, with JetBrains Mono for readouts.