Eliminate the invading force intent on taking Space Station Xorbe in Earth's orbit. If the station is captured then it'll become a staging ground for the invasion of Earth itself. You got a huge arsenal of weapons and defensive mechanisms to stop them.
Drive a single tank against the enemy army. Defend your teleporter and prevent enemy units from escaping through it. Do not leave the battlefield or you will be terminated.
Nobody saw them coming. In the year 2465, aliens destroyed the planet Earth, and only 3,000,000 survivors are launched into space under your command. Help protect humanity against the alien invaders as you find a new Earth somewhere in the galaxy!