On September 1, 1999, X-COM was officially closed by the Council of Funding Nations. The nations of the world now had to deal with the aliens as they saw fit. Most of them chose peace, and the ones that didnít make peace with their new alien overlords were made examples of.
All was well and good for the time being, until January 12, 2000. On that date, massive amounts of alien battleships arrived in orbit. The Alien Battleship is the largest ship the aliens have, capable of downing most X-Com craft from outside their range. Itís typically only used to assault X-Com bases or to impress people. Now a massive fleet of them was orbiting the earth, with countless smaller harvester ships and tankers.
The main alien force had arrived.
The fleet that had subjugated Earth was only an advance group, for finding resource rich worlds. They hit the jackpot with Earth.
Seventy percent of the Earthís surface is covered in liquid water, kilometers deep. There are also massive frozen water reserves at the poles. In the grand scale of the Galaxy, Humanity was a species that evolved and lived solely in Gold Mines. Now, aliens had come to mine the gold.
Humanity as a whole was transported offworld and enslaved. Any resistance movements, whether operated by governments or grass-roots, were swiftly and mercilessly put down. Humanitys genetic materials were read and used to further alien goals.
Humans were sterilized en masse, with further reproduction of the species pending on the judgement of the Alien Overlords.
Meanwhile, the harvesters and tankers set to work. The harvesters slowly and methodically stripped the land of all natural resources. Ores, Plants, Animals, Hydrocarbons and other Organic Compounds
Ö They were all sucked into giant ships and used as raw materials for Alien Industry. Meanwhile, the tankers drained the Earths oceans and lakes, and later, the polar ice caps.
By the time the aliens were done with it, the Earth was a barren, lifeless husk of a planet. It had an atmosphere, but no water to speak of. All metal ores were stripped from it, both on land and the former seabed. What humans were alive spent the rest of their years as slaves, and eventually humanity went extinct.
Billions of years later, the Sun that had shone forever above the pale blue dot expanded into a red giant star. In the process, it engulfed the inner planets, and Earth died a firey death. Then, more billions of years later, the sun shed its outer layers and became a white dwarf. Billions upon billions of years later, when the Sun was a yellow dwarf, the Andromeda Galaxy finally collided with the Milky Way galaxy, and in the process, the sun passed a little too close to a Black Hole, and was swallowed forever into its black depths.
So ends the story of Humanity.