Ufo: Enemy Unknown -

You discover that alien technology relies on Elerium-115 , a stable heavy element not found on Earth, which becomes the most vital resource for humanity's advanced crafts and weapons.

Once X-COM develops the (a powerful interstellar craft), they launch a final mission to Mars. UFO: Enemy Unknown

You recover alien corpses and technology from crash sites to develop laser and plasma weaponry. You discover that alien technology relies on Elerium-115

The story continues in X-COM: Terror from the Deep , where a second wave of aliens awakens from the ocean floor. loses all its bases

If X-COM goes bankrupt, loses all its bases, or fails the Mars mission, the Council of Funding Nations surrenders. In the PlayStation version's defeat cutscene, the aliens violently murder the negotiator sent to discuss terms. Legacy and Continuity