diff --git a/OpenRA.Mods.Cnc/Traits/TransformsNearResources.cs b/OpenRA.Mods.Cnc/Traits/TransformsNearResources.cs
index 74aaa0789a..1d9fd0df56 100644
--- a/OpenRA.Mods.Cnc/Traits/TransformsNearResources.cs
+++ b/OpenRA.Mods.Cnc/Traits/TransformsNearResources.cs
@@ -52,7 +52,7 @@ namespace OpenRA.Mods.Cnc.Traits
 		public TransformsNearResources(Actor self, TransformsNearResourcesInfo info)
 		{
 			resourceLayer = self.World.WorldActor.Trait<IResourceLayer>();
-			delay = Common.Util.RandomDelay(self.World, info.Delay);
+			delay = Common.Util.RandomInRange(self.World.SharedRandom, info.Delay);
 			this.info = info;
 		}
 
diff --git a/OpenRA.Mods.Common/Traits/KillsSelf.cs b/OpenRA.Mods.Common/Traits/KillsSelf.cs
index 6242219aaf..6beb822340 100644
--- a/OpenRA.Mods.Common/Traits/KillsSelf.cs
+++ b/OpenRA.Mods.Common/Traits/KillsSelf.cs
@@ -39,7 +39,7 @@ namespace OpenRA.Mods.Common.Traits
 		public KillsSelf(Actor self, KillsSelfInfo info)
 			: base(info)
 		{
-			lifetime = Util.RandomDelay(self.World, info.Delay);
+			lifetime = Util.RandomInRange(self.World.SharedRandom, info.Delay);
 		}
 
 		protected override void TraitEnabled(Actor self)
diff --git a/OpenRA.Mods.Common/Traits/Render/WithIdleAnimation.cs b/OpenRA.Mods.Common/Traits/Render/WithIdleAnimation.cs
index 2d2e0b527f..e3dc0158c9 100644
--- a/OpenRA.Mods.Common/Traits/Render/WithIdleAnimation.cs
+++ b/OpenRA.Mods.Common/Traits/Render/WithIdleAnimation.cs
@@ -39,7 +39,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			: base(info)
 		{
 			wsb = self.TraitsImplementing<WithSpriteBody>().Single(w => w.Info.Name == Info.Body);
-			ticks = Util.RandomDelay(self.World, info.Interval);
+			ticks = Util.RandomInRange(self.World.SharedRandom, info.Interval);
 		}
 
 		void ITick.Tick(Actor self)
@@ -50,7 +50,7 @@ namespace OpenRA.Mods.Common.Traits.Render
 			if (--ticks <= 0)
 			{
 				wsb.PlayCustomAnimation(self, Info.Sequences.Random(Game.CosmeticRandom));
-				ticks = Util.RandomDelay(self.World, Info.Interval);
+				ticks = Util.RandomInRange(self.World.SharedRandom, Info.Interval);
 			}
 		}
 
diff --git a/OpenRA.Mods.Common/Traits/Sound/AmbientSound.cs b/OpenRA.Mods.Common/Traits/Sound/AmbientSound.cs
index 7bfa2a3d86..435d5440b5 100644
--- a/OpenRA.Mods.Common/Traits/Sound/AmbientSound.cs
+++ b/OpenRA.Mods.Common/Traits/Sound/AmbientSound.cs
@@ -41,7 +41,7 @@ namespace OpenRA.Mods.Common.Traits.Sound
 		public AmbientSound(Actor self, AmbientSoundInfo info)
 			: base(info)
 		{
-			delay = Util.RandomDelay(self.World, info.Delay);
+			delay = Util.RandomInRange(self.World.SharedRandom, info.Delay);
 			loop = Info.Interval.Length == 0 || (Info.Interval.Length == 1 && Info.Interval[0] == 0);
 		}
 
@@ -71,7 +71,7 @@ namespace OpenRA.Mods.Common.Traits.Sound
 			{
 				StartSound(self);
 				if (!loop)
-					delay = Util.RandomDelay(self.World, Info.Interval);
+					delay = Util.RandomInRange(self.World.SharedRandom, Info.Interval);
 			}
 		}
 
@@ -101,7 +101,7 @@ namespace OpenRA.Mods.Common.Traits.Sound
 			currentSounds.Clear();
 		}
 
-		protected override void TraitEnabled(Actor self) { delay = Util.RandomDelay(self.World, Info.Delay); }
+		protected override void TraitEnabled(Actor self) { delay = Util.RandomInRange(self.World.SharedRandom, Info.Delay); }
 		protected override void TraitDisabled(Actor self) { StopSound(); }
 
 		void INotifyRemovedFromWorld.RemovedFromWorld(Actor self) { StopSound(); }
diff --git a/OpenRA.Mods.Common/Traits/World/ActorSpawnManager.cs b/OpenRA.Mods.Common/Traits/World/ActorSpawnManager.cs
index 84d02db504..3b363b11bb 100644
--- a/OpenRA.Mods.Common/Traits/World/ActorSpawnManager.cs
+++ b/OpenRA.Mods.Common/Traits/World/ActorSpawnManager.cs
@@ -93,7 +93,7 @@ namespace OpenRA.Mods.Common.Traits
 			if (spawnPoint == null)
 				return;
 
-			spawnCountdown = Util.RandomDelay(self.World, info.SpawnInterval);
+			spawnCountdown = Util.RandomInRange(self.World.SharedRandom, info.SpawnInterval);
 
 			do
 			{
diff --git a/OpenRA.Mods.Common/Util.cs b/OpenRA.Mods.Common/Util.cs
index 2eb43ae95e..fc23261dc2 100644
--- a/OpenRA.Mods.Common/Util.cs
+++ b/OpenRA.Mods.Common/Util.cs
@@ -198,7 +198,7 @@ namespace OpenRA.Mods.Common
 			}
 		}
 
-		public static int RandomDelay(World world, int[] range)
+		public static int RandomInRange(MersenneTwister random, int[] range)
 		{
 			if (range.Length == 0)
 				return 0;
@@ -206,7 +206,7 @@ namespace OpenRA.Mods.Common
 			if (range.Length == 1)
 				return range[0];
 
-			return world.SharedRandom.Next(range[0], range[1]);
+			return random.Next(range[0], range[1]);
 		}
 
 		public static string FriendlyTypeName(Type t)