Difference between revisions of "Terrain"

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=== Attack ===
 
=== Attack ===
 
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Note that positive river, amphibious, and fort attack modifiers cannot exceed the base penalty.
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Note that positive amphibious, and fort attack modifiers cannot exceed the base penalty. (River modifiers can.)
  
 
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Revision as of 04:45, 3 September 2018

See also: Weather

The terrain of a province can affect the movement and performance of land units and the effectiveness of ground attack, and cause attrition. Harsh terrain tends to favor the defender.

Terrain map.

Base terrain modifiers

  • Movement cost: Movement of Land units is modified by this factor.
  • Attrition: Moving land units 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 Airborne Attack (paradrop) Graphic (normal) Graphic (Winter)
Desert +5% +20% no effect Terrain desert.png Terrain desert winter.png
Forest +50% -20% -10% no effect Terrain forest.png Terrain forest winter.png
Hills +50% -30% -5% no effect Terrain hills.png Terrain hills winter.png
Jungle +50% +30% -30% -25% no effect Terrain jungle.png Terrain jungle winter.png
Marsh +100% +50% -40% no effect Terrain marsh.png Terrain marsh winter.png
Mountain +100% +40% -60% -10% no effect Terrain mountain.png Terrain mountain winter.png
Plains no effect Terrain plains.png Terrain plains winter.png
Urban +20% -30% -50% no effect Terrain urban.png Terrain urban winter.png

Terrain features

In addition to the base terrain, terrain features can apply an additional modifier. The river modifiers apply between two provinces, meaning they do not always appear when a certain province is attacked, but rather when a certain province is attacked from a certain direction. If a river modifier is applied in combat, this also allows other battle tactics.

  • Small river: -30% to attack and -25% to movement.
  • Large river: -60% to attack and -50% to movement.
  • Amphibious landing: -70% to attack.
  • Fort: -15% to attack per level.

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.
  • "Attack" and "defense" refer to the attacking and defending sides and affect both offensive (soft attack, hard attack) and defensive (breakthrough, defense) statistics.
  • 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%
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%
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.