Shield Cost (Unit Statistics)
Determines the base cost (in shields) of building the selected unit. Note that this value is multiplied by a cost factor which determines how many shields it actually costs to produce the selected unit. The human player’s cost factor is always 10. Depending on the difficulty level, the AI’s cost factor can range from 20 (Chieftain level) to 6 (Deity level).
The AI cost factors can be modified via the difficulty levels page.