Is it possible to script for an army to take attrition damage in a region.

[Thor the Bassist]

Could I get a script that checks for a certain building and then creates some attrition damage to an invading army thats in my region?

[HouseOfHam]

You can check a settlement for a certain building, but you can't affect an invading army directly. You could perhaps emulate something using traits...

;------------------------------------------
Trait PoisonedWater
    Characters family
    ExcludeCultures goblin  ; let's say goblins can't be poisoned
    NoGoingBackLevel 3
    AntiTraits SafeDrinkingWater
    
    Level Poisoned_Indigestion
        Description Poisoned_Indigestion_desc
        EffectsDescription Poisoned_Indigestion_effects_desc
        Threshold 1
        
        Effect Influence -1
        Effect Command -1
        Effect TroopMorale -1

    Level Poisoned_Puking
        Description Poisoned_Puking_desc
        EffectsDescription Poisoned_Puking_effects_desc
        Threshold 2
        
        Effect Influence -2
        Effect Loyalty -2
        Effect Command -2
        Effect TroopMorale -2

    Level Poisoned_Dying
        Description Poisoned_Dying_desc
        EffectsDescription Poisoned_Dying_effects_desc
        Threshold 3
        
        Effect Influence -10
        Effect Loyalty -1
        Effect Command -5
        Effect TroopMorale -5

    Level Walking_Corpse
         Description Walking_Corpse_desc
         EffectsDescription Walking_Corpse_effects_desc
         Threshold 4
         
         Effect Influence -10
         Effect Loyalty -10
         Effect Command -10
         Effect TroopMorale -10

 ;------------------------------------------
 Trait SafeDrinkingWater
    Characters family
     Hidden
     AntiTraits PoisonedWater

    Level SafeWater
        Description SafeWater_desc
          EffectsDescription SafeWater_effects_desc
          Threshold 1

  ;------------------------------------------
Trigger PoisonedTrigger
    WhenToTest CharacterTurnEnd

    Condition InEnemyLands
            and SettlementBuildingExists poisonedWells     ; not sure if this would work unless you also EndedInSettlement
  
    Affects PoisonedWater 1 Chance 100
;------------------------------------------

[Thor the Bassist]

Hehe... I think its safe to say that METW will need a scripter at some point.