diff --git a/OpenRA.Mods.Common/Traits/Crates/DuplicateUnitCrateAction.cs b/OpenRA.Mods.Common/Traits/Crates/DuplicateUnitCrateAction.cs
index ba20c0ad1b..39f3c2fb07 100644
--- a/OpenRA.Mods.Common/Traits/Crates/DuplicateUnitCrateAction.cs
+++ b/OpenRA.Mods.Common/Traits/Crates/DuplicateUnitCrateAction.cs
@@ -86,10 +86,26 @@ namespace OpenRA.Mods.Common.Traits
 			collector.World.AddFrameEndTask(w =>
 			{
 				var candidateCells = collector.World.Map.FindTilesInCircle(collector.Location, info.MaxRadius)
-					.Where(c => positionable.CanEnterCell(c)).Shuffle(collector.World.SharedRandom)
+					.Where(c => positionable.CanEnterCell(c));
+
+				var pathFinder = w.WorldActor.TraitOrDefault<IPathFinder>();
+				if (pathFinder != null)
+				{
+					var actorRules = w.Map.Rules.Actors[collector.Info.Name];
+					var locomotorName = actorRules.TraitInfoOrDefault<MobileInfo>()?.Locomotor;
+					if (locomotorName != null)
+					{
+						var locomotor = w.WorldActor.TraitsImplementing<Locomotor>().Single(l => l.Info.Name == locomotorName);
+						candidateCells = candidateCells
+							.Where(c => pathFinder.PathMightExistForLocomotorBlockedByImmovable(locomotor, c, collector.Location));
+					}
+				}
+
+				var shuffledCandidateCells = candidateCells
+					.Shuffle(collector.World.SharedRandom)
 					.ToArray();
 
-				var duplicates = Math.Min(candidateCells.Length, info.MaxAmount);
+				var duplicates = Math.Min(shuffledCandidateCells.Length, info.MaxAmount);
 
 				// Restrict duplicate count to a maximum value
 				if (info.MaxDuplicateValue > 0)
@@ -103,7 +119,7 @@ namespace OpenRA.Mods.Common.Traits
 				{
 					var actor = w.CreateActor(collector.Info.Name, new TypeDictionary
 					{
-						new LocationInit(candidateCells[i]),
+						new LocationInit(shuffledCandidateCells[i]),
 						new OwnerInit(info.Owner ?? collector.Owner.InternalName)
 					});
 
diff --git a/OpenRA.Mods.Common/Traits/Crates/GiveUnitCrateAction.cs b/OpenRA.Mods.Common/Traits/Crates/GiveUnitCrateAction.cs
index 71464a5858..2fa3dcb6fd 100644
--- a/OpenRA.Mods.Common/Traits/Crates/GiveUnitCrateAction.cs
+++ b/OpenRA.Mods.Common/Traits/Crates/GiveUnitCrateAction.cs
@@ -58,10 +58,12 @@ namespace OpenRA.Mods.Common.Traits
 			if (info.ValidFactions.Count > 0 && !info.ValidFactions.Contains(collector.Owner.Faction.InternalName))
 				return false;
 
+			var pathFinder = collector.World.WorldActor.TraitOrDefault<IPathFinder>();
+			var locomotorsByName = collector.World.WorldActor.TraitsImplementing<Locomotor>().ToDictionary(l => l.Info.Name);
 			foreach (var unit in info.Units)
 			{
 				// avoid dumping tanks in the sea, and ships on dry land.
-				if (!GetSuitableCells(collector.Location, unit).Any())
+				if (!GetSuitableCells(collector.Location, unit, pathFinder, locomotorsByName).Any())
 					return false;
 			}
 
@@ -80,9 +82,11 @@ namespace OpenRA.Mods.Common.Traits
 		{
 			collector.World.AddFrameEndTask(w =>
 			{
+				var pathFinder = w.WorldActor.TraitOrDefault<IPathFinder>();
+				var locomotorsByName = w.WorldActor.TraitsImplementing<Locomotor>().ToDictionary(l => l.Info.Name);
 				foreach (var unit in info.Units)
 				{
-					var location = ChooseEmptyCellNear(collector, unit);
+					var location = ChooseEmptyCellNear(collector, unit, pathFinder, locomotorsByName);
 					if (location != null)
 					{
 						var actor = w.CreateActor(unit, new TypeDictionary
@@ -101,19 +105,33 @@ namespace OpenRA.Mods.Common.Traits
 			base.Activate(collector);
 		}
 
-		IEnumerable<CPos> GetSuitableCells(CPos near, string unitName)
+		IEnumerable<CPos> GetSuitableCells(CPos near, string unitName, IPathFinder pathFinder, Dictionary<string, Locomotor> locomotorsByName)
 		{
-			var ip = self.World.Map.Rules.Actors[unitName].TraitInfo<IPositionableInfo>();
+			var actorRules = self.World.Map.Rules.Actors[unitName];
 
-			for (var i = -1; i < 2; i++)
-				for (var j = -1; j < 2; j++)
-					if (ip.CanEnterCell(self.World, self, near + new CVec(i, j)))
+			Locomotor locomotor = null;
+			if (pathFinder != null)
+			{
+				var locomotorName = actorRules.TraitInfoOrDefault<MobileInfo>()?.Locomotor;
+				locomotor = locomotorName != null ? locomotorsByName[locomotorName] : null;
+			}
+
+			var ip = actorRules.TraitInfo<IPositionableInfo>();
+			for (var i = -1; i <= 1; i++)
+			{
+				for (var j = -1; j <= 1; j++)
+				{
+					var cell = near + new CVec(i, j);
+					if (ip.CanEnterCell(self.World, self, cell) &&
+						(locomotor == null || pathFinder.PathMightExistForLocomotorBlockedByImmovable(locomotor, cell, near)))
 						yield return near + new CVec(i, j);
+				}
+			}
 		}
 
-		CPos? ChooseEmptyCellNear(Actor a, string unit)
+		CPos? ChooseEmptyCellNear(Actor a, string unit, IPathFinder pathFinder, Dictionary<string, Locomotor> locomotorsByName)
 		{
-			return GetSuitableCells(a.Location, unit)
+			return GetSuitableCells(a.Location, unit, pathFinder, locomotorsByName)
 				.Cast<CPos?>()
 				.RandomOrDefault(self.World.SharedRandom);
 		}
diff --git a/OpenRA.Mods.Common/Traits/World/SpawnStartingUnits.cs b/OpenRA.Mods.Common/Traits/World/SpawnStartingUnits.cs
index 1c27807a4e..a016bea376 100644
--- a/OpenRA.Mods.Common/Traits/World/SpawnStartingUnits.cs
+++ b/OpenRA.Mods.Common/Traits/World/SpawnStartingUnits.cs
@@ -21,7 +21,7 @@ namespace OpenRA.Mods.Common.Traits
 	[TraitLocation(SystemActors.World)]
 	[Desc("Spawn base actor at the spawnpoint and support units in an annulus around the base actor. " +
 		"Both are defined at MPStartUnits. Attach this to the world actor.")]
-	public class SpawnStartingUnitsInfo : TraitInfo, Requires<StartingUnitsInfo>, NotBefore<LocomotorInfo>, ILobbyOptions
+	public class SpawnStartingUnitsInfo : TraitInfo, Requires<StartingUnitsInfo>, NotBefore<PathFinderInfo>, ILobbyOptions
 	{
 		public readonly string StartingUnitsClass = "none";
 
@@ -102,13 +102,29 @@ namespace OpenRA.Mods.Common.Traits
 			if (unitGroup.SupportActors.Length == 0)
 				return;
 
-			var supportSpawnCells = w.Map.FindTilesInAnnulus(p.HomeLocation, unitGroup.InnerSupportRadius + 1, unitGroup.OuterSupportRadius);
+			var supportSpawnCells = w.Map
+				.FindTilesInAnnulus(p.HomeLocation, unitGroup.InnerSupportRadius + 1, unitGroup.OuterSupportRadius)
+				.ToList();
 
+			var pathFinder = w.WorldActor.TraitOrDefault<IPathFinder>();
+			var locomotorsByName = w.WorldActor.TraitsImplementing<Locomotor>().ToDictionary(l => l.Info.Name);
 			foreach (var s in unitGroup.SupportActors)
 			{
 				var actorRules = w.Map.Rules.Actors[s.ToLowerInvariant()];
 				var ip = actorRules.TraitInfo<IPositionableInfo>();
-				var validCell = supportSpawnCells.Shuffle(w.SharedRandom).FirstOrDefault(c => ip.CanEnterCell(w, null, c));
+				var validCells = supportSpawnCells.Where(c => ip.CanEnterCell(w, null, c));
+
+				if (pathFinder != null)
+				{
+					var locomotorName = actorRules.TraitInfoOrDefault<MobileInfo>()?.Locomotor;
+					var locomotor = locomotorName != null ? locomotorsByName[locomotorName] : null;
+
+					if (locomotor != null)
+						validCells = validCells
+							.Where(c => pathFinder.PathMightExistForLocomotorBlockedByImmovable(locomotor, c, p.HomeLocation + unitGroup.BaseActorOffset));
+				}
+
+				var validCell = validCells.RandomOrDefault(w.SharedRandom);
 
 				if (validCell == CPos.Zero)
 				{