In the beginning, I just tried out different setting options without any system, but then I gradually tried to figure out how two of the pianobots could easily play together and if it sounded somewhat harmonical. Then I tried the same with a third (or fourth) pianobot. :D All in all, this was a nice, systematic audio-puzzle game that tried something different, and I thought that was very good! :D That's why I recommended your Ludum Dare 42 entry in one of our compilation articles about the jam. One minute of gameplay can also be seen in the accompanying video. :)
Best wishes,
Sebastian