still have no clue how to install this on linux, still enjoying the newgrounds version tho
Try downloading 'RushdownRivalsLINUX2.appimage' instead of the zip version. Then put that file somewhere that you can remember. If you right click it, go to the properties and find a check box that says it's an 'executable' and enable it. It should hopefully launch. If not I think the os is specifically for Ubuntu.