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.
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
The story continues in X-COM: Terror from the Deep , where a second wave of aliens awakens from the ocean floor. UFO: Enemy Unknown
Destroying the Alien Brain severs the link between the invaders and their leadership, causing the alien forces on Earth to collapse and saving humanity.
Once X-COM develops the (a powerful interstellar craft), they launch a final mission to Mars. You discover that alien technology relies on Elerium-115
Soldiers must fight through the Martian surface and into the underground alien complex.
As the Commander, you start with basic human ballistics while fighting various alien species, such as the physically frail but psionic and the brutish Mutons . The "story" is largely driven by your research: Legacy and Continuity The story continues in X-COM:
Late-game research uncovers the truth: the invasion is being orchestrated by the , a highly advanced, psionic race that has enslaved other species to serve as their military arm. Their primary base in the solar system is located in the Cydonia region of Mars. The Final Assault: Cydonia