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Alpha Centauri features a Unit Design Workshop which is very flexible in comparison to other Civ games. For each unit, the workshop presents you with choices for each of a unit's weapon (attack strength), armor (defense strength), chassis (speed and terrain movement), reactor (hit points and build cost), and up to two special abilities (but only one until the discovery of Neural Grafting).

[edit] Unit cost

Unit cost is calculated using the following formula:

C = W × (A + S) × 10 ÷ (2(R + 1))

Where:

• C is the total unit cost in Minerals;
• W is the unit's Weapon value (Equipment for non-combat units);
• A is the unit's Armor value;
• S is the unit's Speed expressed in move points;
• R is the unit's Reactor value.

It can be determined that units with a high value in all three areas (Weapon, Armor and Speed) will be much more expensive than units with a high value in just two. Therefore, it is advantageous to design your units for specific tasks rather than attempting to create all-round utility units. For example: a unit built for defending a base will need a high Armor value, but has little use for heavy Weapons or a high Speed, while for an attacker, a powerful Weapon is tantamount to effectiveness, while Armor may not be as important (the idea being that your opponent will be destroyed before they have a chance to fire back).

The basic unit cost formula is subject to several modifiers:

• Weapon value may never be less than half the unit's Armor value
• Final cost is halved for units with a Speed of 1
• Armor value is halved when calculating the cost of sea units, and the final cost is halved again
• Armor value is doubled when calculating the cost of any air unit; the final cost is quartered for combat air units
• Add 25% to final cost for each unit of Special Ability cost
• Add 10 Minerals if both Weapon and Armor values are greater than 1
• Add another 10 Minerals if Weapon, Armor and Speed values are all greater than 1
• C_min = (R × 2 − R ÷ 2) × 10 where Cmin is the unit's minimum final cost.