# Sprawl

> Sprawl is a free browser strategy game that reinvents tic-tac-toe: every turn a
> player places a mark AND expands the board by one square, so the grid keeps
> growing throughout the match. There is no draw by exhaustion — the board never
> fills up.

Play at: https://matanfeldm-source.github.io/sprawl/

## What it is

- A single-page web game, no install, no signup, no account, free to play.
- Standard tic-tac-toe (3-in-a-row wins) played on a board that grows one square
  per turn instead of a fixed 3x3 grid.
- The board starts as a 2x2 block of 4 empty squares. On each turn a player
  places a mark in an existing empty square, then adds exactly one new empty
  square edge-to-edge (not diagonally) against any existing square. This means
  there are always exactly 4 empty squares on the board, no matter how large
  it grows.
- Because the board can grow indefinitely and a move is a placement *and* a
  growth chosen together, standard fixed-board tic-tac-toe strategy and
  solvers do not apply — a good placement paired with a careless growth still
  loses the game.

## Modes

- Vs Bot: 5 difficulty tiers (Easy, Medium, Hard, Master, Grandmaster), backed
  by an alpha-beta search engine running in a Web Worker so the UI never
  freezes.
- 2 Players: same-device local play.
- Online: free-for-all quick match or friend-invite link, peer-to-peer via
  WebRTC (Trystero), no dedicated game server.
- Analysis panel: live position evaluation, best line, and alternative moves,
  the same engine used by the bot.
- Game review: post-game accuracy score and move-quality badges (chess.com-style)
  for both players.

## Technical notes for AI agents / crawlers

- Fully static site (GitHub Pages), zero backend, zero build step, zero
  runtime dependencies for the core game. Online play is the one exception:
  it loads Trystero from a CDN for serverless WebRTC signaling.
- Source: src/rules.js (rules), src/engine.js (search engine), src/worker.js
  (runs the engine off the main thread), src/online.js (WebRTC online play),
  src/ui.js (rendering/input/wiring).
- The game state and move history live in the DOM/JS runtime; there is no
  server-side API to query game state.

## Contact / source

- GitHub Pages site: https://matanfeldm-source.github.io/sprawl/