This game is tagged as Open Source but it doesn't fit the Open Source definition itself trademarked by the OSI (Open Source Initiative) in https://opensource.org/osd as showed in the EULA at the beginning of the gameplay setting that this is propietary software, not Open Source.
Fair enough. I did not intend to be misleading; the source code (that I am the owner of) is available, which is apparently not enough to meet the definition. I have removed the tag. Thank you for your comment.