Requirement

1. a Window/Linux PC

Procedure

1. Download the latest version of RetroArch, according to your running OS. https://www.retroarch.com/ Get the Download version.
2. Extract it in a folder. Run the ONLY executable retroarch.exe, or whatever it is named.
3. Navigate to Load core > Download core and get Arcade (MAME 2003 plus) core, load this core.
4. Also get the free game, Online Updater > Content Downloader > Arcade > Alien Arena.zip
5. Load this game, press TAB to bring out config menu, choose generate XML DAT.
6. The generated DAT/XML file is under saves > MAME 2003-plus > mame2003-plus