Aliens 3 ROM Download for SEGA Genesis (Genesis) on Emulator Games. Play Aliens 3 game that is available in the United States of America (USA) version only on this website. Aliens 3 is a SEGA Genesis emulator game that you can download to your computer or play online within your browser. You can also download free ROMs such as Aliens - Thanatos Encounter, Aliens and Roswell Conspiracies - Aliens, Myths & Legends as shown below. Aliens 3 works on all your devices in high quality.