Military units may get promotions which increase their abilities. A promotion can mean either of two closely related concepts. One is the process of taking a promotion; the other is the resultant change to the unit, which is signified by icons shown with it when it is selected.
You can see the promotions a unit has when you select it. Each promotion it has is depicted via a unique icon that is associated with that promotion; see the articles for specific promotions to see their icon. (An example w/ picture would be nice here.)
Means to Promotions
There are several ways in which a military unit may get a promotion. First, many kinds of military units have one or more free promotions that they get when they are built. Sometimes a free promotion is inherent to the unit itself, for example, mechanized infantry come with the march promotion. Sometimes a free promotion is granted based on a leader trait (i.e. combat I for aggressive leaders). Or it may be granted by a building (i.e. duns give guerrilla I.)
A second way in which a unit can get a promotion is via a unit upgrade. Any promotion which is inherent to the unit-type which a unit is upgraded to will be added to the unit. For example, if you upgrade an infantry to a mechanized infantry, it will gain the march promotion if it does not already have it.
The final way in which promotions are given is via the experience system. See below.
Experience and Promotions
When a unit has certain levels of experience, it becomes eligible to get a promotion. When this is the case, when it is selected the promotions that it is eligible will have buttons shown on the unit display. You can click any active button to take the promotion represented on it.
The amount of experience needed for a promotion always increases for each addition promotion. There are two cases: if the civilization has a charismatic leader, 25% less experience (fractions round up) is needed for each promotion. Note that the experience system is completely independent of any free promotions a unit may get; having a free promotion does not give experience, nor does it count as a having a promotion for the purpose of getting experience-based promotions.
Experience Required for Nth Experience-based Promotion 1 2 3 4 5 6 7 8 9 10 11 12 ... N charismatic 2 4 8 13 20 28 37 48 61 75 91 108 ... ceil((N^2+1)*0.75) others 2 5 10 17 26 37 50 65 82 101 122 145 ... N^2+1
Taking a Promotion
When a unit takes a promotion, there are several effects. First, it immediately gains the promotion, and thus the promotion's effects. Thus you may take a promotion and then attack in the same turn. Second, it is unfortified—any fortification bonus it gets from immobility is lost. Finally, it is healed half of its hitpoint deficit.
List of Promotions
This is a list of promotions available.
- Barrage (I - III)
- City Garrison (I - III)
- City Raider (I - III)
- Combat (I - VI)
- Drill (I - IV)
- Flanking (I - II)
- Guerrilla (I - III)
- Interception (I - II)
- Medic (I - III)
- Navigation(I - II)
- Range (I - II)
- Woodsman (I - III)
|Civilization IV |
|Warlords • Beyond the Sword • Colonization†|
|† Total conversion remake of the game Sid Meier's Colonization using Civilization IV engine|