Terrain

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See also: Weather

The terrain of the world map can affect the movement and combat performance of units, and cause attrition (equipment loss, not manpower loss). Harsh terrain tends to favor the defender.

Terrain map.

Types[edit]

  • 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.
Terrain Movement cost Attrition (equipment loss) Attack Enemy air superiority Graphic (normal) Graphic (Winter)
Desert +5% +20% Terrain desert.png Terrain desert winter.png
Forest +50% -20% -10% Terrain forest.png Terrain forest winter.png
Hills +50% -30% -5% Terrain hills.png Terrain hills winter.png
Jungle +50% +30% -30% -25% Terrain jungle.png Terrain jungle winter.png
Marsh +100% +50% -40% Terrain marsh.png Terrain marsh winter.png
Mountain +100% +40% -60% -10% Terrain mountain.png Terrain mountain winter.png
Plains Terrain plains.png Terrain plains winter.png
Urban +20% -30% -50% Terrain urban.png Terrain urban winter.png
Ocean
Lake

Province[edit]

The terrain type of a province is shown in the bottom left when selecting it. When provinces visually contain multiple terrain types, the most dominant one is used. All terrain effects except movement cost are based on it.

Paths[edit]

A path between two adjacent provinces is the straight line between their centers. It is traced on a pixel grid, 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]

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: -15% to attack/defense per level.

The river adjuster apply 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 in all directions but with each flanking attack the bonus gets diminished.

Unit-specific adjusters[edit]

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[1] 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.

Note that positive amphibious, and fort attack adjusters cannot exceed the base penalty. (River adjusters can.)


List of terrain attack adjusters by unit
Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert River Amphibious Fort
Anti-Air Combat -10% -20% -20% -20% -40%
Anti-Tank Combat -20% -25% -20% -20% -40% +10%
Artillery Combat -20% -25% -20% -20% -40% +10%
Bicycle Battalion Combat
Cavalry Combat -5% -5% -10% -5% -10% -40%
Engineer Company Support (+10%[2]) (+10%[3]) +25% +10% (+20%[4])
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% +40% +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% -70%
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 Infantry Combat -10% -5% -10% -20% -10% -10% -20%
Motorized Rocket Artillery 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
List of terrain defense adjusters by unit
Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert River Amphibious Fort
Anti-Air Combat
Anti-Tank Combat
Artillery Combat
Bicycle Battalion Combat
Cavalry Combat
Engineer Company Support +25% +10% (+10%[2]) +25% +25% +25% (+35%[3]) +25% (+35%[4])
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 Infantry Combat
Motorized Rocket Artillery 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
List of terrain movement adjusters by unit
Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert River Amphibious Fort
Anti-Air Combat -10% -20% -20% -20%
Anti-Tank Combat -20% -5% -20% -20% -30% -20%
Artillery Combat -20% -5% -20% -20% -30% -20%
Bicycle Battalion Combat +10% +5% +20% +20% +5% +5% -5% -5%
Cavalry Combat -5%
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%
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 Infantry Combat -50% -50% -30% -10%
Motorized Rocket Artillery Combat -50% -5% -20% -50% -50% -20%
Mountaineers Combat +10% +20%
Paratroopers Combat
Recon Company Support +10% +10% +10% +10% +10% +10% +10% +10%
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
  1. This means Engineer Company's fort defense bonus of +25% does not work
  2. 2.0 2.1 requires Engineer Company IV
  3. 3.0 3.1 requires Engineer Company III
  4. 4.0 4.1 requires Engineer Company II