Open source? yes
Source code: https://github.com/magarena/magarena/releases/download/1.81/Magarena-1.81.zip
Description: it's a single-player fantasy card game played against a computer opponent with the rules based on Magic: The Gathering.
This has sat in accepted for inclusion for over a year. Clearly, there is a lack of demand for the inclusion of this software, nobody has stepped up to provide a completed patch, maintain it, and properly integrate it. Closing as a result. Feel free to reopen but only when someone offers a patch via our proper patch submission methods and volunteers to be maintainer.