Civ IV Colonization - Combat and Promotions
The combat system in Civ IV Colonization has changed a lot from the classic version of Colonization, most notably with the implementation of unit health and experience points. Players familiar with the Civ IV combat system will find themselves right at home. For those not familiar with it, here's a short summary:
(Skip down to Promotions)
Healing
In the 1994 version of Colonization you either lost or won a battle, there was no in-between. That has now changed with the unit health system. It's still possible to completely destroy units, in fact this is often the case when you lose a battle. Some units though, may manage to withdraw from a battle. They suffer great damage, but at least they live to fight another day. Victorious units may also suffer damage depending on how tough a battle is. Units have the ability to heal, which is best done in a friendly settlement or with a Surgeon present on the same tile.
Experience
Units gain experience from winning battles. Experience is measured by experience points (XP). When a unit reaches a certain level of XPs, it receives a promotion. When it reaches the next level required, it receives another promotion, and so on. Promotions specialize units and make them stronger, for example they may provide attack/defense bonuses, increased movement or visibility range, the ability to heal other units faster etc. The ability for units to heal and attain promotions will, over time, make some of them great assets to your overall military force.
After reaching a specific amount of total XPs (from all combats) your colony will produce a Great General. Attaching the Great General to a unit will provide an instant boost of 20 XPs to that unit if it is the only unit occupying the tile. If there are multiple units occupying the tile, each unit gets an equal share of the 20 points. In addition, units led by a Great General get access to special promotions.
Unit stacks
Another important factor to consider is unit stacks, meaning the combination of units on the same tile. When the enemy attacks a tile with multiple units on it, the computer will automatically pick your strongest unit for that battle. Having a unit with the Charge and Formation promotions would make it stronger in combat against both Dragoons and Cannons. It's not easy to attain numerous promotions for a single unit, and so one way to achieve a similar effect would be to stack two units together, one with Formation and one with Charge.
The same would be true for terrain bonuses, and of course having at least one Surgeon would benefit that stack greatly when it's time to lick one's wounds.
Example: Combat odds
How combat works
When your attacking unit is active, right-click and hold the pointer over a hostile unit. The odds of you winning that battle will become visible in the lower left corner of the screen. The odds are determined by:
Your unit's strength + modifiers
vs.
Enemy unit's strength + modifiers
Strength
Strength is the unit's base strength minus any damage it has suffered. For example, a fully healed Dragoon has a strength of 4, while a somewhat injured one might have a strength of 3,5.
Modifiers
Modifiers are unit-specific bonuses, terrain bonuses, promotion bonuses, fortification bonuses, and bonuses from rebel sentiment. They are listed as %. Modifiers are added together and then applied to the strength. In other words, a unit with a strength of 4 and two modifiers (+20%, +25%) would get: 4 x 1,45 = 5,8 total.
Unit-specific bonus
This refers to a bonus for a specific unit type. For example, Dragoons receive +50% vs cannons and have a 30% withdrawal chance, but they receive no defensive bonuses. The King's Regular receives a +25% settlement attack bonus, but it receives no defensive bonuses.
Terrain bonuses
Terrain bonuses, if applicable, derive from the terrain of the defending tile. Hills provide a +25% defensive bonus, forests +50% and forested hills +75%.
Keep in mind, however, that some units do not receive any defensive bonuses.
Promotion bonuses
Bonuses from promotions, such as +10% strength for Veteran 1 or +20% settlement defense for Minuteman 1. A full list of available promotions follows below.
Fortification bonus
When you fortify a unit, it gets +5% per turn
for a maximum of 25%. Units behind a Stockade, Fort or Fortress get defensive bonuses from those buildings.
Rebel Sentiment bonuses
When defending a settlement against the King's forces during the War of Independence, your units receive a bonus related to the overall Rebel Sentiment in your colonies.
To sum it up, it is vital to know the different units' strengths and weaknesses. Learning which units to use in different circumstances, and thinking ahead when promoting units, may just be the deciding factor and lead your troops to victory.
Available promotions (Civ IV Colonization version 1.01)
| Name | Bonus | Requires | |
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Amphibious | No combat penalty for attacking from ocean No combat penalty for attacking across river |
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Bomb I | +20% settlement attack | |
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Bomb II | +25% settlement attack | |
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Bomb III | +30% settlement attack | + |
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Canister Shot I | +20% vs. gunpowder units | |
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Canister Shot II | +25% vs. gunpowder units | |
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Canister Shot III | +30% vs. gunpowder units | + |
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Charge | +25% vs. siege weapons |  |
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Explorer I | -1 terrain movement cost | |
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Explorer II | +1 visibility range | |
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Explorer III | +1 movement Can use enemy roads |
+ |
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Formation | +25% vs. mounted units | |
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Grenadier I | +20% settlement attack | |
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Grenadier II | +25% settlement attack | |
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Grenadier III | +30% settlement attack +10% vs. gunpowder units |
+ |
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Leadership | Gains +100% experience from combat | |
|
Lead by Great General | Promotions not available to other units | |
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Looter | +50% gold from pillaging | |
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Minuteman I | +20% settlement defense | |
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Minuteman II | +25% settlement defense | |
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Minuteman III | +30% settlement defense +10% vs. melee units |
+ |
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Mountaineer I | +15% hills attack +15% hills defense |
|
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Mountaineer II | +25% hills attack and defense Double movement on hills |
|
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Mountaineer III | +35% hills attack and defense Can attack multiple times per turn |
+ |
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Navigation I | +1 visibility range | |
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Navigation II | +1 movement range | |
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Navigation III | +1 movement range | + |
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Ranger I | +20% Forest/Light Forest attack +20% Forest/Light Forest defense |
|
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Ranger II | +25% Forest/Light Forest attack and defense Double movement in Forest/ Light Forest |
|
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Ranger III | +30% Forest/Light Forest attack and defense Can attack multiple times per turn |
+ |
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Skirmisher I | +10% withdrawal chance | |
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Skirmisher II | +20% withdrawal chance | |
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Skirmisher III | +30% withdrawal chance | + |
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Solid Shot I | +5% settlement bombard damage | |
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Solid Shot II | +10% settlement bombard damage | |
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Solid Shot II | +15% settlement bombard damage | + |
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Surgeon I | Heals units in same tile extra 10% per turn | |
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Surgeon II | Heals units in adjacent tiles extra 10% per turn | |
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Surgeon III | Heals units in same and adjacent tiles extra 15%/turn Can heal while moving |
+ |
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Swamp Fox I | +20% marsh and jungle attack +20% marsh and jungle defense |
|
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Swamp Fox II | +25% marsh and jungle attack and defense Double movement in marsh and jungle |
|
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Swamp Fox III | +30% marsh and jungle attack and defense Can attack multiple times per turn |
+ |
|
Veteran I | +10% strength | |
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Veteran II | +10% strength | |
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Veteran III | +10% strength | |
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Veteran IV | +10% strength Heals extra 10% per turn in neutral lands |
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Veteran V | +10% strength Heals extra 10% per turn in enemy lands |
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Veteran VI | +25% strength | + |