if the cerberus damages a non-vehicle or a vehicle that does not fly, the damage is reduced by anywhere between 1 and 4

src/main/scala/net/psforever/objects/global/GlobalDefinitionsProjectile.scala

@@ -1783,7 +1783,7 @@ object GlobalDefinitionsProjectile {
     spitfire_aa_ammo_projectile.Lifespan = 5f
     ProjectileDefinition.CalculateDerivedFields(spitfire_aa_ammo_projectile)
     spitfire_aa_ammo_projectile.Modifiers = List(
-      //FlakHit,
+      CerberusTurretWrongTarget,
       FlakBurst,
       MaxDistanceCutoff
     )

src/main/scala/net/psforever/objects/vital/projectile/ProjectileDamageModifierFunctions.scala

@@ -1,9 +1,10 @@
 // Copyright (c) 2020 PSForever
 package net.psforever.objects.vital.projectile
 
+import net.psforever.objects.GlobalDefinitions
 import net.psforever.objects.ballistics._
 import net.psforever.objects.equipment.ChargeFireModeDefinition
-import net.psforever.objects.sourcing.PlayerSource
+import net.psforever.objects.sourcing.{PlayerSource, VehicleSource}
 import net.psforever.objects.vital.base._
 import net.psforever.objects.vital.damage.DamageModifierFunctions
 import net.psforever.objects.vital.interaction.DamageInteraction
@@ -354,6 +355,19 @@ case object ShieldAgainstRadiation extends ProjectileDamageModifiers.Mod {
   }
 }
 
+/** The Cerberus turret can not target any entities besides flying vehicles.
+  * An exception to this rule, however, happens when retaliating against something that damaged it first. */
+case object CerberusTurretWrongTarget extends ProjectileDamageModifiers.Mod {
+  def calculate(damage: Int, data: DamageInteraction, cause: ProjectileReason): Int = {
+    data.target match {
+      case v: VehicleSource if GlobalDefinitions.isFlightVehicle(v.Definition) =>
+        damage
+      case _ =>
+        damage - (math.random() * 3d).toInt - 1
+    }
+  }
+}
+
 /* Functions */
 object ProjectileDamageModifierFunctions {
   /**