The Butterfly Effect is a free and open source game that uses realistic physics simulations to combine lots of simple mechanical elements to achieve a simple goal in the most complex way possible.

This is a fully playable game of alpha quality, well on its way to a shiny 1.0 release.

Features

The Butterfly Effect has been over five years in the making. That means that even though the game has been designed by hobbyists, the game is rich in features:

• Many different objects: cola bottles, balloons, butterflies, domino stones, springs, dynamite, seesaws, penguins
• Many different types of puzzles
• Works on Linux, Windows and MacOX
• Playable in English, Dutch, German, Russian, French, Danish, Swedish, Turkish, Ukrainian and several other languages. Note that not all languages are 100% yet
• Using vector graphics - all images always rendered at the highest quality
• in Milestone B, there are roughly 70 levels. All levels are playable, but a few levels may need a bit more polish.

Screenshots

(the screenshots are clickable)

Download

We have packages of the latest version available for the following Linux distributions and Windows:

If you need them, please refer to our installation instructions. If you want to know what’s most popular, please take a look at our download statistics.

if you are a packager and want to add TBE to a distribution or build for another platform, do not hesitate to contact the developers

Open Source

This game is released under the GPLv2 license. That The Butterfly Effect is open source, means that you can build the game yourself, look how we did it and modify the code or the levels. We’d love for you to submit your changes back to us - we love feedback and will try to incorporate your changes into the next version of the game.

That’s what open source is about: as a community we try to make the best game possible!

The Butterfly Effect also wouldn’t have been possible without other open source projects, including:

• Qt library for the graphical user interface
• Box2D library for physics simulations
• CMake/CPack tools for configuring and building applications
• NSIS the Nullsoft Installer is a program to build Windows installer tools
• Inkscape is a program to draw vector graphics
• Openclipart.org is a website to share clipart graphics
• git is a tool for source code management. It is the backbone of GitHub

To be honest, we also use a few commercial offerings, including:

• GitHub a website that hosts source code and websites
• Coverity a tool to find software bugs through static analysis
• Pareon Verify a tool to find software bugs though dynamic analysis
• Transifex a website to help translating of software

Help out with translations

We use the Transifex project to translate the user interface. You can sign up and get started at the thebutterflyeffect page.

Note that levels and the UI have different translation mechanisms, but both are handled through Transifex.

Help out with new or improved levels

If you have ideas for levels, we’d love to hear from you!

Probably the easiest way to let us know about your ideas, is to create a login on the GitHub website and create an issue for TBE. We’ll work with you to make your ideas happen. Note that as of Milestone B we have a level editor again, so you can design your own levels!

Add more code

If you are a C++ programmer, we’d love to hear from you - there’s always more things that can be coded!

Create a login on the GitHub website, clone the repo and start hacking. We love patches and pull requests!

Found any bugs? Or you have feedback?

Oh boy. Does TBE still contain bugs?

Please log in to GitHub and file an issue or contact the developers the-butterfly-effect by e-mail.