diff --git a/OpenRA.Mods.Common/Traits/Infantry/TakeCover.cs b/OpenRA.Mods.Common/Traits/Infantry/TakeCover.cs
index bc620d2e06..59331fc5cd 100644
--- a/OpenRA.Mods.Common/Traits/Infantry/TakeCover.cs
+++ b/OpenRA.Mods.Common/Traits/Infantry/TakeCover.cs
@@ -92,7 +92,7 @@ namespace OpenRA.Mods.Common.Traits
 			if (!IsProne)
 				return 100;
 
-			if (damage.DamageTypes.IsEmpty)
+			if (damage == null || damage.DamageTypes.IsEmpty)
 				return 100;
 
 			var modifierPercentages = info.DamageModifiers.Where(x => damage.DamageTypes.Contains(x.Key)).Select(x => x.Value);
diff --git a/OpenRA.Mods.Common/Traits/Infantry/TerrainModifiesDamage.cs b/OpenRA.Mods.Common/Traits/Infantry/TerrainModifiesDamage.cs
index e02073b008..f822ffdadd 100644
--- a/OpenRA.Mods.Common/Traits/Infantry/TerrainModifiesDamage.cs
+++ b/OpenRA.Mods.Common/Traits/Infantry/TerrainModifiesDamage.cs
@@ -42,7 +42,7 @@ namespace OpenRA.Mods.Common.Traits
 
 		int IDamageModifier.GetDamageModifier(Actor attacker, Damage damage)
 		{
-			if (attacker.Owner.IsAlliedWith(self.Owner) && damage.Value < 0 && !Info.ModifyHealing)
+			if (!Info.ModifyHealing && attacker.Owner.IsAlliedWith(self.Owner) && damage != null && damage.Value < 0)
 				return FullDamage;
 
 			var world = self.World;