Terrain

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This article describes terrain in land provinces.
For naval terrain, see naval terrain.

See also: Weather

The terrain of land provinces can affect the movement and combat performance of units, and cause attrition. Harsh terrain tends to favor the defender.

Terrain map.
Legend:
desert = "red background with ⛭"
hills = "cornsilk background with △"
mountain = "light gray background with ▲"
ocean = "blue background with ~"
lakes = "blue background with no symbol"
marsh = "olive background with ⚶"
forest = "spring green background with ♧"
jungle = "yellow green background with ♣"
plains = "orange background with no symbol"
urban = "dark gray background with ⚑"

]]

Types[edit | edit source]

Each land province has a terrain type, which is shown when the province is selected.

  • Combat width: Maximum amount of battalions that can fight in a province. "+Additional attacks" is how much combat width will be added for each extra direction of attack into the province.
  • Movement cost: Increases the distance units have to travel by this factor.
  • Attrition: When at war, land units moving from this terrain type suffer this amount of attrition.
  • Attack: Adjuster to the attacker's soft/hard attack and breakthrough when the defender is in this terrain.
  • Enemy air superiority: If the enemy has air superiority, their bonus is reduced by this amount.
  • Sickness: Army leaders may become temporarily unwell when units are in this terrain.
  • Supply flow penalty factor: Reduces the flow of hub supply into a province with this terrain.
  • Truck attrition factor: Increases the rate of attrition for trucks used to motorize supply hubs in this terrain.
Terrain Combat width Movement cost Attrition (equipment loss) Attack Enemy air superiority sickness Supply flow penalty factor Truck attrition factor Graphic (normal) Graphic (Winter)
Desert 90(+45) +5% +15% 1 0.14 0.5 Terrain desert.png Terrain desert winter.png
Forest 84(+42) +50% -15% -10% 0.08 0.2 Terrain forest.png Terrain forest winter.png
Hills 80(+40) +50% -25% -5% 0.1 0.2 Terrain hills.png Terrain hills winter.png
Jungle 84(+42) +50% +20% -30% -25% 1 0.16 3.0 Terrain jungle.png Terrain jungle winter.png
Marsh 78(+26) +100% +35% -40% 1 0.16 4.0 Terrain marsh.png Terrain marsh winter.png
Mountain 75(+25) +100% +30% -50% -10% 0.12 1.0 Terrain mountain.png Terrain mountain winter.png
Plains 90(+45) Terrain plains.png Terrain plains winter.png
Urban 96(+32) +20% -30% -50% -0.2 Terrain urban.png Terrain urban winter.png
Lake

Paths[edit | edit source]

A path between two adjacent provinces is the straight line between their centers. It is traced on a pixel grid[1], making diagonal lines noticeably longer than north-south and east-west lines. The terrain along this path (along with its distance) determines its movement cost.

The path may consist of the source and target province's terrain in varying proportions or even different terrains altogether. For example the path between two coastal mountain provinces at a fjord might consist of 40% mountain and 60% ocean, resulting in +40% movement cost for this path instead of +100% in a pure mountain range.

The path also determines whether direction-dependent terrain features apply.

Terrain features[edit | edit source]

Terrain features can apply adjusters and modifiers in addition to the base terrain. They stack multiplicatively with base terrain values. They only affect the attacker because some of them depend on the path and the defender might fight against attackers from different directions. The attack adjuster applies to the attacker's soft/hard attack and the defense adjuster to their breakthrough.

  • Small river: -30% to attack/defense and -25% to movement.
  • Large river: -60% to attack/defense and -50% to movement.
  • Amphibious landing: -70% to attack/defense.
  • Fort (land and naval): -15% to attack/defense per level.

The river adjuster applies when a path intersects a river. If a river modifier is applied in combat, this also allows other battle tactics. The amphibious landing penalty applies when a unit attacks a land province from a sea province. The movement cost of an amphibious landing is a fixed length.

The fort adjuster applies to land forts in all directions. With each flanking attack the bonus gets diminished. Naval forts reduce the attack when attacking in an amphibious landing, and when attacking across a strait.

Unit-specific adjusters[edit | edit source]

Units may have specific adjusters in addition to the base terrain and terrain feature adjusters. The net adjuster for a division is the average of its combat battalions, plus the sum of the adjusters of its support battalions. Among the regular terrain adjusters, the attack value modifies the attacker's attack and breakthrough, and the defense value modifies the defender's attack and defense.

For terrain feature adjusters (except amphibious and forts), the attack value modifies the attacker's attack, and the defense value modifies the attacker's breakthrough. The amphibious and fort adjusters ignore their defense value[2] and use the attack value for both attack and breakthrough. The unit's adjuster stacks additively with the terrain and terrain feature adjuster respectively. Divisions lacking manpower have proportionately smaller bonuses and penalties.

Units move at the slowest speed of a combat battalion (adjusted for terrain). Recon units can increase the max speed of units for some terrain.

Note that positive amphibious and fort attack adjusters cannot exceed the base penalty, while river adjusters can.

Attack[edit | edit source]

List of terrain attack adjusters by unit
Unit Type Forest.png
Forest
Hills.png
Hills
Mountain.png
Mountain
Plains.png
Plains
Urban.png
Urban
Jungle.png
Jungle
Marsh.png
Marsh
Desert.png
Desert
River.png
River

Amphibious.png
Amphibious

Fort.png
Fort
Amphibious Armor Combat −20% -10% -10% -40% -30% +30% +40% +60%
Amphibious Mechanized Combat -20% -5% -20% -30% +20% +30% +50%
Anti-Air Combat −10% −20% −20% −20% −40%
Anti-Tank Combat −20% −25% −20% −20% −40% +10%
Armored Car Combat −20% -10% -30% −30% −10% −20% −40%
Artillery Combat −20%

−25%

−20% −20% −40% +10%
Bicycle Battalion Combat
Camel Combat −5% −5% −10% −5% −10% +5% −40%
Cavalry Combat

−5%

−5% −10% −5% −10% −40%
Engineer Company Support (+10%[3]) (+10%[4]) +25% +10% (+20%[5])
Field Hospital Support
Heavy SP Anti-Air Combat −40% −20% −30%

−50%

−60% −40% −40% −80%
Heavy SP Artillery Combat −40% −20% −30% −50% −60% −40% −40% −80%
Heavy Tank Combat −40% −20%

−30%

−50% −60%

−40%

−40% −80%

+10%

Heavy Tank Destroyer Combat −40% −20% −30% −50% −60% −40% −40% −80% +5%
Infantry Combat
Light SP Anti-Air Combat −20% −10% −40% −30% −10% −20% −60%
Light SP Artillery Combat −20% −10% −40% −30% −10% −20% −60%
Light Tank Combat

−20%

−10% −40% −30% −10% −20% −40%
Light Tank Destroyer Combat −20%

−10%

−40% −30% −10%

−20%

−60%
Logistics Company Support
Maintenance Company Support
Marines Combat +30% +30% +50%
Mechanized Infantry Combat −20% −5%

−20%

−30% −10% −20% −40%
Medium SP Anti-Air Combat −30% −10% −20% −40% −40% −10% −20% −70%
Medium SP Artillery Combat −30% −10% −20% −40% −40% −10% −20% −70%
Medium Tank Combat −30% −10% −20% −40% −40% −10% −20% −80%
Medium Tank Destroyer Combat −30%

−10%

−20%

−40%

−40% −10% −20% −70%
Military Police Support
Modern SP Anti-Air Combat −30% −10% −20% −40% −40% −10% −20% −70%
Modern SP Artillery Combat −30% −10% −20% −40% −40% −10% −20% −70%
Modern Tank Combat −30% −10% −20% −40%

−40%

−10% −20% −70%
Modern Tank Destroyer Combat −30% −10% −20% −40% −40%

−10%

−20% −70%
Motorized Anti-Air Combat −10% −20% −20% −20% −40%
Motorized Anti-Tank Combat -20% -25%

-20%

-20% -40% +10%
Motorized Artillery Combat −20%

−25%

−20% −20% −40% +10%
Motorized Infantry Combat −10% −5%

−10%

−20% −10% −10% −20%
Motorized Rocket Artillery Combat −20% −25% −20% −20% −40% +10%
Motorized Rocket(Katyusha} Combat −10%

−25%

−20% −20% −40% +10%
Mountaineers Combat +20% +35%
Paratroopers Combat
Recon Company Support
Rocket Artillery Combat −20% −25% −20% −20% −40% +10%
Signal Company Support
Super Heavy SP Anti-Air Combat −50% −30% −40% −60% −70% −50% −50% −100%
Super Heavy SP Artillery Combat −50% −30% −40% −60% −70% −50% −50% −100%
Super Heavy Tank Destroyer Combat −50% −30% −40% −60% −70% −50% −50% −100% +30%
Super-Heavy Tank Combat −50% −30% −40%

−60%

−70% −50% −50% −100% +50%
Support Anti-Air Support
Support Anti-Tank Support
Support Artillery Support
Support Rocket Artillery Support
Light Flame Tank Company Support +5% +5% +5% +10% +10% +5% +10% +10% +10%
Medium Flame Tank Company Support +10% +5% +5% +15% +15% +5% +10% +10% +20%
Heavy Flame Tank Company Support +10% +5% +10% +10% +5% +5% +5% +25%

Defense[edit | edit source]

List of terrain defense adjusters by unit
Unit Type Forest.png
Forest
Hills.png
Hills
Mountain.png
Mountain
Plains.png
Plains
Urban.png
Urban
Jungle.png
Jungle
Marsh.png
Marsh
Desert.png
Desert
River.png
River
Amphibious.png
Amphibious
Fort.png
Fort
Amphibious Mechanized Combat -5%
Amphibious Tank Combat -10%
Anti-Air Combat
Anti-Tank Combat
Armored Car Combat
Artillery Combat
Bicycle Battalion Combat
Camel Combat +5%
Cavalry Combat
Engineer Company Support +25%

+10%

(+10%[3]) +25% +25% +25% (+35%[4]) +25% (+35%[5])
Field Hospital Support
Heavy SP Anti-Air Combat −20%
Heavy SP Artillery Combat −20%
Heavy Tank Combat −20%
Heavy Tank Destroyer Combat −20%
Infantry Combat
Light SP Anti-Air Combat −10%
Light SP Artillery Combat −10%
Light Tank Combat −10%
Light Tank Destroyer Combat −10%
Logistics Company Support
Maintenance Company Support
Marines Combat
Mechanized Infantry Combat −5%
Medium SP Anti-Air Combat −10%
Medium SP Artillery Combat −10%
Medium Tank Combat −10%
Medium Tank Destroyer Combat

−10%

Military Police Support
Modern SP Anti-Air Combat −10%
Modern SP Artillery Combat −10%
Modern Tank Combat −10%
Modern Tank Destroyer Combat −10%
Motorized Anti-Air Combat
Motorized Anti-Tank Combat
Motorized Artillery Combat
Motorized Infantry Combat -5%
Motorized Rocket Artillery Combat
Motorized Rocket (Katyusha) Combat
Mountaineers Combat +5% +10%
Paratroopers Combat
Recon Company Support
Rocket Artillery Combat
Signal Company Support
Super Heavy SP Anti-Air Combat

−20%

Super Heavy SP Artillery Combat −20%
Super Heavy Tank Destroyer Combat −20%
Super-Heavy Tank Combat

−20%

Support Anti-Air Support
Support Anti-Tank Support
Support Artillery Support
Support Rocket Artillery Support

Movement[edit | edit source]

List of terrain movement adjusters by unit
Unit Type Forest.png
Forest
Hills.png
Hills
Mountain.png
Mountain
Plains.png
Plains
Urban.png
Urban
Jungle.png
Jungle
Marsh.png
Marsh
Desert.png
Desert

River.png
River

Amphibious.png
Amphibious
Fort.png
Fort
Amphibious Mechanized Combat
Amphibious Tank Combat -40% -10% -40%
Anti-Air Combat −10%

−20%

−20%

−20%

Anti-Tank Combat −20% −5% −20% −25% −30% −20%
Armored Car Combat

−40%

-10% −50% −20% +15% −20%
Armored Car Recon Company Support +5% +10% +5% +15% +5%

+15%

+10%

Artillery Combat −20% −5% −20% −20% −30% −20%
Bicycle Battalion Combat +10% +5% +20% +20% +5% +5% −5%

−5%

Camel Combat −5% −5% +15% −5% +5% +10%
Cavalry Combat −5%
Cavalry Recon Company Support +5% +10% +10%

+5%

+10% +10% +5% +10%
Engineer Company Support +5% +20% +25%
Field Hospital Support
Heavy SP Anti-Air Combat −40%

−40%

−20% −40%
Heavy SP Artillery Combat −40% −40%

−20%

−40%
Heavy Tank Combat

−40%

−40% −20% −40%
Heavy Tank Destroyer Combat

−40%

−40% −20% −40%
Infantry Combat
Light SP Anti-Air Combat −40%

−40%

−10% −20%
Light SP Artillery Combat −40% −40%

−10%

−20%
Light Tank Combat

−40%

−40% −10% −20%
Light Tank Destroyer Combat −40% −40% −10% −20%
Light Tank Recon Company Support +10% +10%

+10%

+10% +10% +10% +10% +10%
Logistics Company Support
Maintenance Company Support
Marines Combat
Mechanized Infantry Combat −20%
Medium SP Anti-Air Combat −40% −40% −10% −20%
Medium SP Artillery Combat −40% −40% −10% −20%
Medium Tank Combat −40% −40% −10% −20%
Medium Tank Destroyer Combat −40% −40% −10% −20%
Military Police Support
Modern SP Anti-Air Combat −40% −40% −10% −20%
Modern SP Artillery Combat −40% −40% −10% −20%
Modern Tank Combat −40% −40% −10% −20%
Modern Tank Destroyer Combat −40%

−40%

−10% −20%
Motorized Anti-Air Combat

−50%

−50% −20% −20%
Motorized Anti-Tank Combat −50% −5% −20% −50% −30% −20%
Motorized Artillery Combat −50% −5% −20%

−50%

−30% −20%
Motorized Infantry Combat −50% −50% −30% −10%
Motorized Recon Company Support +5% +10% +10% +15% +5% +10% +20% +10%
Motorized Rocket Artillery Combat

−50%

−5%

−20%

−50%

−30%

−20%

Motorized Rocket (Katyusha) Combat −50% −5% −20% −50% −50% −20%
Mountaineers Combat +10% +20%
Paratroopers Combat
Rocket Artillery Combat

−20%

−5% −20% −20% −30% −20%
Signal Company Support
Super Heavy SP Anti-Air Combat

−40%

−40% −20% −40%
Super Heavy SP Artillery Combat −40% −40% −20%

−50%

Super Heavy Tank Destroyer Combat −40% −40% −20% −50%
Super-Heavy Tank Combat −40% −40% −20% −50%
Support Anti-Air Support
Support Anti-Tank Support
Support Artillery Support
Support Rocket Artillery Support
Light Flame Tank Company Support +10%
Medium Flame Tank Company Support +10%
Heavy Flame Tank Company Support +10%


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  1. wp:Bresenham's_line_algorithm
  2. This means Engineer Company's fort defense bonus of +25% does not work
  3. 3.0 3.1 requires Engineer Company IV
  4. 4.0 4.1 requires Engineer Company III
  5. 5.0 5.1 requires Engineer Company II