Run Down

Mobile battle royale. 100 players. Meteors rain from orbit. Last one standing wins.

No storm. No circle. Just rocks falling from the sky.

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Gameplay

• 100 players spawn across a 1600×1600 map
• Meteor bombardment replaces the shrinking zone — 6 phases, each tightening the safe shelter radius
• Stay inside the shelter zone or take continuous meteor damage
• Loot weapons, shoot enemies, build cover
• Bot AI fills the lobby — bots flee meteors, engage enemies, and loot drops

Controls (mobile)

Input	Action
Left joystick	Move
Right side tap	Aim + shoot
Reload button	Reload active weapon
Build toggle	Switch to build mode
Weapon slots (1–3)	Tap to switch

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Architecture

Game Loop (50ms tick)

Input → moveHumanPlayer → tickBots → tickBombardment → applyMeteorDamage → checkWinCondition → Zustand → render

The tick function (GameEngine.ts) is pure — takes (GameState, InputState, deltaMs) → returns GameState. No side effects, no mocks needed in tests.

Meteor Phases

Phase	Shelter Radius	Damage/hit	Strike interval
1	800	25 HP	8s
2	500	35 HP	6s
3	300	50 HP	4s
4	150	65 HP	3s
5	50	80 HP	2s
6	10	100 HP	1s

Bot AI Priority

1. Flee to shelter (if outside zone)
2. Engage nearest enemy (if within 400 units)
3. Pick up loot (if within 60 units)
4. Wander randomly

Weapon Stats

Type	Damage	Fire Rate	Mag	Range
Assault Rifle	35	5/s	30	400
SMG	17	10/s	35	200
Shotgun	110	0.8/s	5	120
Sniper	100	0.5/s	4	800
Pickaxe	20	0.9/s	∞	60

Rarity multiplier applies to damage: Common 1.0× → Legendary 1.5×

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Project Structure

src/
├── core/
│   ├── gameEngine/       — pure tick function, shot resolution
│   ├── meteor/           — 6-phase bombardment, shelter zone shrink
│   └── physics/          — collision detection, bullet hit
├── services/
│   ├── ai/               — bot decision loop (flee, engage, loot, wander)
│   ├── weapons/          — fire rate, spread, reload timers
│   └── state/            — Zustand global store, initial state factory
├── screens/
│   ├── LobbyScreen.tsx
│   ├── GameScreen.tsx
│   └── GameOverScreen.tsx
├── components/
│   ├── GameMap.tsx
│   ├── HUD.tsx
│   ├── Joystick.tsx
│   ├── PlayerSprite.tsx
│   ├── MeteorZoneOverlay.tsx
│   ├── LootDropView.tsx
│   └── BuildPieceView.tsx
├── utils/                — math helpers (lerp, clamp, normalize, distance)
└── types/                — TypeScript interfaces (GameState, Player, Weapon…)

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Setup

Prerequisites

• Node.js 18+
• React Native CLI
• Android Studio (Android) or Xcode 14+ (iOS)

Install

git clone https://github.com/cloudygetty-ai/run-down.git
cd run-down
npm install
cp config.example.js config.js

Run

# iOS
npm run ios

# Android
npm run android

# Metro only
npm start

Browser demo

Open demo.html directly in Chrome — no server needed. Runs at native 4K on high-DPI displays.

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Development

npm run type-check   # tsc --noEmit
npm run lint         # eslint src/
npm test             # jest (co-located *.test.ts files)
npm test -- --coverage

Tests are co-located: Module.ts → Module.test.ts. All tests must pass and lint must be clean before merge.

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Path Aliases

Configured in tsconfig.json and babel.config.js:

Alias	Resolves to
@core/*	src/core/*
@services/*	src/services/*
@screens/*	src/screens/*
@components/*	src/components/*
@utils/*	src/utils/*
@types/*	src/types/*

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Tech Stack

Layer	Library
Framework	React Native 0.72
Language	TypeScript 5.0 (strict)
State	Zustand 4.4
Persistence	AsyncStorage
Testing	Jest + React Native Testing Library
Linting	ESLint + @react-native config

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License

MIT