Soldiers are used extensively in Galactic Civilizations II. They are used to control ships (though this is not deducted from the planet's population since it is negligible), and also during planetary invasions. Their efficiency is controlled by different parameters, such as soldiering. Every taxpayer has the capability to become a soldier . One unit of soldiers (1 on the planetary invasion screen, normal transports carry 1000 units) represents 1 million people (therefore the transport module can carry 500 million people, and the advanced module carries 1 billion people).