Terrain

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Revision as of 15:22, 16 February 2019 by Bitmode (talk | contribs) (add engineer company II bonus to table)
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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. Harsh terrain tends to favor the defender.

Terrain map.

Types

  • 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: Modifier 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 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

Province

The terrain type of a province is the one that appears the most in its area. All terrain effects except movement cost are based on it.

Paths

A path between two adjacent provinces is the straight line between their centers. The terrain along this path (along with its distance) determines its movement cost. The path also determines whether direction-dependent terrain features apply.

Terrain features

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 modifiers 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 modifiers

Units may have specific modifiers in addition to the base terrain and terrain feature modifiers.

Notes:

  • These are as shown in the "Adjusters" section in-game.
  • The net modifier for a division is the average of its combat battalions, plus the sum of the modifiers for its support battalions.
  • Among the regular terrain modifiers, the attack modifiers modify the attacker's attack and breakthrough, and the defense modifiers modify the defender's attack and defense.
  • For rivers the attacker's breakthrough is modified by defense modifiers. For amphibious and forts only attack modifiers are used. Since the defender isn't affected by terrain features these modifiers don't apply.
  • The attack and defense modifiers stack additively with the base terrain value, while the movement modifier is multiplicative with the base terrain movement cost.
  • River, amphibious, and fort modifiers stack with that of the terrain type proper.
  • Understrength divisions have proportionately smaller bonuses, but penalties are unaffected.

Attack

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

Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert Small river Large river Amphibious Fort
Anti-Air Combat -10% -20% -20% -20% -20% -40%
Anti-Tank Combat -20% -25% -20% -20% -20% -40% +10%
Artillery Combat -20% -25% -20% -20% -20% -40% +10%
Bicycle Battalion Combat
Cavalry Combat -5% -5% -10% -5% -10% -40%
Engineer Company Support +25% +10% (+20%[1])
Field Hospital Support
Heavy SP Anti-Air Combat -40% -20% -30% -50% -60% -40% -40% -40% -80%
Heavy SP Artillery Combat -40% -20% -30% -50% -60% -40% -40% -40% -80%
Heavy Tank Combat -40% -20% -30% -50% -60% -40% -40% -40% -80% +10%
Heavy Tank Destroyer Combat -40% -20% -30% -50% -60% -40% -40% -40% -80% +5%
Infantry Combat
Light SP Anti-Air Combat -20% -10% -40% -30% -10% -20% -20% -60%
Light SP Artillery Combat -20% -10% -40% -30% -10% -20% -20% -60%
Light Tank Combat -20% -10% -40% -30% -10% -20% -20% -40%
Light Tank Destroyer Combat -20% -10% -40% -30% -10% -20% -20% -60%
Logistics Company Support
Maintenance Company Support
Marines Combat +30% +40% +40% +50%
Mechanized Infantry Combat -20% -5% -20% -30% -10% -20% -20% -40%
Medium SP Anti-Air Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Medium SP Artillery Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Medium Tank Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Medium Tank Destroyer Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Military Police Support
Modern SP Anti-Air Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Modern SP Artillery Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Modern Tank Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Modern Tank Destroyer Combat -30% -10% -20% -40% -40% -10% -20% -20% -70%
Motorized Infantry Combat -10% -5% -10% -20% -10% -10% -10% -20%
Motorized Rocket Artillery Combat -10% -25% -20% -20% -20% -40% +10%
Mountaineers Combat +20% +35%
Paratroopers Combat
Recon Company Support
Rocket Artillery Combat -20% -25% -20% -20% -20% -40% +10%
Signal Company Support
Super Heavy SP Anti-Air Combat -50% -30% -40% -60% -70% -50% -50% -50% -100%
Super Heavy SP Artillery Combat -50% -30% -40% -60% -70% -50% -50% -50% -100%
Super Heavy Tank Destroyer Combat -50% -30% -40% -60% -70% -50% -50% -50% -100% +30%
Super-Heavy Tank Combat -50% -30% -40% -60% -70% -50% -50% -50% -100% +50%
Support Anti-Air Support
Support Anti-Tank Support
Support Artillery Support
Support Rocket Artillery Support

Defense

Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert Small river Large river Amphibious Fort
Anti-Air Combat
Anti-Tank Combat
Artillery Combat
Bicycle Battalion Combat
Cavalry Combat
Engineer Company Support +25% +10% +25% +25% +25% +25% +25% (+35%[1])
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

Movement

Unit Type Forest Hills Mountain Plains Urban Jungle Marsh Desert Small river Large river Amphibious Fort
Anti-Air Combat -10% -20% -20% -20% -20%
Anti-Tank Combat -20% -5% -20% -20% -30% -20% -20%
Artillery Combat -20% -5% -20% -20% -30% -20% -20%
Bicycle Battalion Combat +10% +5% +20% +20% +5% +5% -5% -5% -5%
Cavalry Combat -5%
Engineer Company Support +5% +20% +25% +25%
Field Hospital Support
Heavy SP Anti-Air Combat -40% -40% -20% -40% -40%
Heavy SP Artillery Combat -40% -40% -20% -40% -40%
Heavy Tank Combat -40% -40% -20% -40% -40%
Heavy Tank Destroyer Combat -40% -40% -20% -40% -40%
Infantry Combat
Light SP Anti-Air Combat -40% -40% -10% -20% -20%
Light SP Artillery Combat -40% -40% -10% -20% -20%
Light Tank Combat -40% -40% -10% -20% -20%
Light Tank Destroyer Combat -40% -40% -10% -20% -20%
Logistics Company Support
Maintenance Company Support
Marines Combat
Mechanized Infantry Combat -20% -20%
Medium SP Anti-Air Combat -40% -40% -10% -20% -20%
Medium SP Artillery Combat -40% -40% -10% -20% -20%
Medium Tank Combat -40% -40% -10% -20% -20%
Medium Tank Destroyer Combat -40% -40% -10% -20% -20%
Military Police Support
Modern SP Anti-Air Combat -40% -40% -10% -20% -20%
Modern SP Artillery Combat -40% -40% -10% -20% -20%
Modern Tank Combat -40% -40% -10% -20% -20%
Modern Tank Destroyer Combat -40% -40% -10% -20% -20%
Motorized Infantry Combat -50% -50% -30% -10% -10%
Motorized Rocket Artillery Combat -50% -5% -20% -50% -50% -20% -20%
Mountaineers Combat +10% +20%
Paratroopers Combat
Recon Company Support +10% +10% +10% +10% +10% +10% +10% +10% +10%
Rocket Artillery Combat -20% -5% -20% -20% -30% -20% -20%
Signal Company Support
Super Heavy SP Anti-Air Combat -40% -40% -20% -40% -40%
Super Heavy SP Artillery Combat -40% -40% -20% -50% -50%
Super Heavy Tank Destroyer Combat -40% -40% -20% -50% -50%
Super-Heavy Tank Combat -40% -40% -20% -50% -50%
Support Anti-Air Support
Support Anti-Tank Support
Support Artillery Support
Support Rocket Artillery Support

Upgrades

The Engineer Company II upgrade grants +10% attack and defense in forts, Engineer Company III grants +10% attack and defense in rivers, and Engineer Company IV grants +10% attack and defense in urban terrain.

  1. 1.0 1.1 requires Engineer Company II