Mission_Asteroid_Sierra_On_Line ROM Download can be obtained free for Atari 800 on EmuGames.net only. Play emulator game in English for the USA region. Mission_Asteroid_Sierra_On_Line is a Atari 800 ROM that you can download to your computer or play online within your browser. You can also download roms such as DMG Gariba Boui and Grand Theft Auto Chinatown Wars that work on all devices including desktop and mobile. Be sure to rate the game if you enjoyed playing this ROM.