diff --git a/OpenRA.Mods.Common/Traits/Mobile.cs b/OpenRA.Mods.Common/Traits/Mobile.cs
index 78a2848592..790c424fa5 100644
--- a/OpenRA.Mods.Common/Traits/Mobile.cs
+++ b/OpenRA.Mods.Common/Traits/Mobile.cs
@@ -129,7 +129,7 @@ namespace OpenRA.Mods.Common.Traits
 	}
 
 	public class Mobile : PausableConditionalTrait<MobileInfo>, IIssueOrder, IResolveOrder, IOrderVoice, IPositionable, IMove, ITick,
-		IFacing, IDeathActorInitModifier, INotifyAddedToWorld, INotifyRemovedFromWorld, INotifyBlockingMove, IActorPreviewInitModifier, INotifyBecomingIdle, IObservesVariables
+		IFacing, IDeathActorInitModifier, INotifyAddedToWorld, INotifyRemovedFromWorld, INotifyBlockingMove, IActorPreviewInitModifier, INotifyBecomingIdle
 	{
 		readonly Actor self;
 		readonly Lazy<IEnumerable<int>> speedModifiers;
@@ -752,8 +752,11 @@ namespace OpenRA.Mods.Common.Traits
 				Nudge(self, blocking, true);
 		}
 
-		IEnumerable<VariableObserver> IObservesVariables.GetVariableObservers()
+		public override IEnumerable<VariableObserver> GetVariableObservers()
 		{
+			foreach (var observer in base.GetVariableObservers())
+				yield return observer;
+
 			if (Info.RequireForceMoveCondition != null)
 				yield return new VariableObserver(RequireForceMoveConditionChanged, Info.RequireForceMoveCondition.Variables);
 		}