Mass Production is a "Key Technology" in the free game C-evo, inaugurating . The "Modern resources" or rare minerals, Cobalt, Mercury, and Uranium, essential for building spaceship parts to win the game, now appear in what were otherwise dead lands. All three classes of future military units can now be designed with the Line Production Unit Special Feature that doubles the construction cost for the first unit built in any city but halves it (rounding down fractions) for all subsequent units built consecutively in that city.