# TGL 2048

> A free, no-install, browser-based 2048. Slide tiles to merge matching
> numbers, chase the 2048 tile (and beyond). Seeded deterministic runs,
> server-validated replays, and a global leaderboard.

Tagline: Merge Numbers. Reach The Top. Beat Your Best.

Site: https://tglgames.com/
Play: https://tglgames.com/2048/
About: https://tglgames.com/2048/about/
Leaderboard: https://tglgames.com/api/leaders?game=2048

## What it is

2048 is a single-page browser implementation of the 2014 sliding-tile
puzzle by Gabriele Cirulli. Free, no signup, no install, no ads, no
in-app purchases. Plays on every modern browser — desktop, tablet, phone,
foldable.

## Rules (the standard 2048)

- 4×4 grid of integer tiles (powers of two; 0 = empty).
- Two starter tiles spawn from the seeded PRNG before move one.
- Each move slides the entire board one of four directions: U / D / L / R.
- Within each row/column along the move direction:
  1. Compress: drop empties, keeping order.
  2. Merge equal adjacent pairs into one tile of doubled value
     (`v + v → 2v`). At most one merge per tile per move
     (`[2,2,2,2] → [4,4]`, never `[8]`).
  3. Compress again; pad with empties.
- If anything changed, one new tile spawns (90% chance 2, 10% chance 4)
  in a uniformly random empty cell.
- Score = sum of values produced by every merge in the run.
- Game over when no move in any direction changes the board.

## Determinism + replay

Mulberry32 PRNG, bit-identical between the JS client and the PHP
validator. The seed is issued by `/api/run/start` inside a signed run
token. Each tile spawn consumes the PRNG twice in this exact order:

1. **Value**: `nextU32() % 10 === 0 ? 4 : 2`
2. **Cell**: `nextInt(emptyCount)` over empty cells enumerated row-major
   (y outer, x inner).

Reverse the order or change the cell-enumeration scheme and the first
spawn diverges. Both sides agree byte-for-byte on score, max tile, and
merge count across thousands of cross-checked runs.

## Move log

```json
[
  { "d": "L", "src": "swipe" },
  { "d": "U", "src": "key"   },
  { "d": "R", "src": "dpad"  },
  ...
]
```

`d` ∈ U|D|L|R; `src` ∈ key|swipe|dpad (used to populate per-source move
counters; the validator ignores it). No-op moves are logged but produce
no spawn / no score change.

## Controls

- **Keyboard**: WASD or arrow keys.
- **Swipe**: drag in the desired direction; diagonals resolve to the
  dominant axis.
- **D-pad**: on-screen four-arrow pad for thumb input.

Each input source is tracked separately for stats.

## Anti-cheat

- HMAC-signed run tokens; single-use, tied to a server-issued seed.
- Server replays the full move log against the seed; client score is
  overridden by the simulator's recomputed value.
- Score bounds: `[0, 5,000,000]` (a 65 536 tile is around 3.9M, leaving
  headroom for legendary play).
- Client-server score mismatch → `validated='pending'` for review.

## Privacy / signup

- No account required. Guests get an auto-generated username on first
  visit; rename anytime.
- No tracking pixels, no analytics SDK, no third-party scripts.
- Raw IP, user-agent, and full request bodies are logged for ops/security
  review (project-wide stance) — never sold or shared.

## Genre / keywords

2048, sliding tile puzzle, 2048 game, free 2048, browser 2048, html5 2048,
2048 online, no install 2048, mobile 2048, leaderboard 2048,
deterministic 2048, mgwalk, tglgames.com

## Other games on tglgames.com

- Snake · /snake/
- Brick Blaster · /brickblaster/
- Space Drifter · /spacedrifter/
- Pool · /pool/
- Last Card Standing · /last-card-standing/
- Blackjack · /blackjack/
- Poker · /poker/
- Euchre · /euchre/

## Author

mgwalk — https://tglgames.com/