Then, when I discovered surreal numbers, I realized that playing games is mathematics. --- John Conway

Hackenbush: Pocket Edition

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This project is an implementation of finite Red-Blue Hackenbush, mainly for mobile devices. Hackenbush is a simple and fun puzzle game that led to the discovery of a very large, fascinating algebraic structure, the surreal numbers. It was invented by John Conway.

The aim of this project is to promote combinatorial game theory by giving fans of Hackenbush an easy way to demonstrate it, and potentially to teach it to new players as well.

Where to Play

You can download an APK on the releases page, install via the Play Store or build it yourself by opening the project in Godot 3. While performance and stability is not guaranteed, here is a browser version, too!

Features

The project is still in development, but these features are already implemented:

• <img src="https://github.com/file-acomplaint/hackenbush/blob/main/Sprites/1P.png" height="30"> Computer Opponent
• <img src="https://github.com/file-acomplaint/hackenbush/blob/main/Sprites/2P.png" height="30"> Local 2-Player Mode
• Rudimentary Level Editor
• Calculation of the surreal number associated with a position
• 32 Levels

The issues page lists some future feature ideas.

Heritage

Hackenbush: Pocket Edition is made in Godot Engine and steals the difficult part of its logic from a great Hackenbush implementation for Mac and PC, by Tom R. Davis. The pixel font is by Kawika Heftel, licensed under CC0. Thanks!

Since Tom Davis' version is under the GPL 2.0 license, so is this project.

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Further Reading

• Hackenbush: A window to a new world of math is a video explaining the rules of the game while walking the viewer through the discovery of surreal numbers. A must watch!
• Winning Ways for Your Mathematical Plays is a great introduction to combinatorial game theory in book format.

And apparently, Critical Acclaim

This game won the German National Multimedia Award mb21, which you can read more about here in German. Many thanks to the jury!