The world is being threatened. There is only one solution to this problem and that is that one race has to go. It will not be easy, but instead of fighting you will try it in a different manner. Biological warfare is your weapon. All the germs are going to the enemy to kill them all. But they don't just get there, you need to guide them through a difficult maze of pipes and steps. Help them reach their destination, so they can start their work quickly.
Use the arrow keys to move, the X to take control of a colonist and the C to let him/her go.