> For the complete documentation index, see [llms.txt](https://docs.harmony.one/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.harmony.one/home/developers/showcases/games/harmony-puzzle.md).

# Harmony Puzzle

The Harmony Puzzle game challenges players to solve 100 levels of gameplay ([see video introduction](https://www.youtube.com/watch?v=zU_LhrDcQyM)). Players' moves are registered as transactions on the Harmony blockchain serving as an immutable record of their score. 

The puzzle was originally featured during Harmony’s IEO launch on Binance in 2019 where it reached over 81,000 users. Users of the Harmony Puzzle will experience first-hand Harmony’s 2-second finality time and near zero transaction fees.

The Harmony Puzzle's [Android app](https://github.com/harmony-one/android-puzzle) is open sourced on our Github.  

![](/files/-MOHVImQRloQQvAkd_xd)