Twenty Squares is a CLI video game, that is to say that it runs in a computer's terminal. It's also cross-platform, so it can be run on Windows 64-bit and 32-bit, as well as on Unix-based systems like MacOS and Linux. As for the API used to develop it, it's the C programming language.

It can be found as a mini-game in Treasure Venture.

It's based upon the oldest game known to mankind: a five millennia old mesopotamian board game, known today as the Game of Twenty Squares or the Royal Game of Ur. Its purpose is to provide a "classic" version of the game, as well as a new take on it, that exploits possibilities brought by a computer.

The game has four levels:

1. Classic Infinite.
2. Classic Dispatch.
3. Deadly Sins Infinite.
4. Deadly Sins Dispatch.

On these notes, I reserve special thanks to Irving Finkel of the British Museum and Tom Scott, who was his guest in the Museum's introductory video on the Royal Game of Ur. This video is how I came to learn of the game, and I've used the simple rules described in it to make the first level.