: This term also refers to the specific ROM set version required for that emulator. Using the wrong ROM version often leads to games not working. As documentation warns: "Each version of an arcade emulator must be used with ROMs that have the same exact version number" . The "FBA Arcade Set v0.2.97.29" is the required version for the FBA 2012 libretro core (often called lr-fbalpha2012 ), a version ported to RetroArch that became highly popular for its performance.