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.
The aliens are back to snack on farmer brains. This time they are filled with ACID BLOOD! Look out, the acid will harm your defenses. Strategically place the crop circles to make the maze then set up your defenses and blast the aliens back to outer space.
You escaped the orbital space station and survived the explosion. Dr Rycroft left co-ordinates and now you need to investigate what experiments he performed on you. Beware though, he has surrounded himself with hi-tech defenses.
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.
Defend your invasion forces from attacking ships while they retake solar systems from a malicious computer virus. Use your special vessel, the Nautilus, to manufacture ships to assist you in the battle.