Terrain and Climate matters a lot when engaging in a battle and can easily decide wars. It also affect the RGO output of a province and is often strongly correlating with life rating. Each province in the game has a certain terrain, which cannot be altered in any way.
Terrain Statistics
- Defense: Defending armies get this number as a bonus to all combat die rolls.
| Name | Movement Cost | Defense | Farm Size | Farm Efficiency | Mine Size | Mine Efficiency | Supply Limit Modifier | Combat Width | Infrastructure |
|---|---|---|---|---|---|---|---|---|---|
| Arctic | 1.0 | 0 | 50% | 80% | 100% | 80% | 1 | 100% | -1 |
| Coastal Desert | 1.0 | 0 | 75% | 100% | 100% | 100% | 2 | 100% | |
| Desert | 1.5 | 0 | 50% | 80% | 100% | 100% | 1 | 100% | |
| Farmlands | 1.2 | 0 | 120% | 100% | 100% | 100% | 10 | 100% | |
| Forest | 1.2 | +1 | 100% | 100% | 100% | 100% | 6 | 80% | |
| Hills | 1.2 | +1 | 100% | 100% | 100% | 100% | 6 | 67% | -1 |
| Jungle | 1.3 | +2 | 100% | 80% | 100% | 80% | 2 | 75% | -2 |
| Marsh | 1.4 | +1 | 100% | 80% | 100% | 80% | 2 | 75% | -2 |
| Mountains | 1.4 | +2 | 100% | 75% | 100% | 100% | 2 | 34% | -3 |
| Plains | 1.0 | 0 | 100% | 100% | 100% | 100% | 10 | 100% | |
| Steppe | 1.0 | 0 | 100% | 100% | 100% | 100% | 8 | 100% | |
| Woods | 1.1 | +1 | 100% | 100% | 100% | 100% | 6 | 80% |
Supply Limit
Supply Limit determines how many regiments you can have in a province before suffering increased attrition. It is affected by ownership, occupation, terrain and Industrial technology. Having more troops placed in the province, than the supply limit allows, gives the troops attrition.
Modifiers
- Infrastructure increases Supply Limit by 3.8 at 100%. This means level 6 Infrastructure will increase Supply Limit by 0.63.
- Chemistry & Electricity tech tree increases the Supply Limit.
Multipliers
- A multiplier is applied to the Supply Limit depending on the status of the province. For provinces that you own and control, the multiplier is x2.5.
Climate
- Harsh Climates give +5 Attrition, while Inhospitable Climates give +10 Attrition.
Attrition
Attrition is a loss of troops by wearing down. It is applied if there are more troops in a province than the current Supply limit. The attrition gets exponentially larger, the more the stack goes over the supply limit. Laying siege to a province also give additional 2% attrition. It is applied every month, or when a unit enters a province. Units in battle do not suffer attrition.
Attrition is stated as a percentage of the total stack, which is lost every time it is applied. It is capped at 15%