diff --git a/OpenRa.Game/Game.cs b/OpenRa.Game/Game.cs
index 77fa4f53e0..cfd4760341 100644
--- a/OpenRa.Game/Game.cs
+++ b/OpenRa.Game/Game.cs
@@ -191,14 +191,16 @@ namespace OpenRa.Game
 			if (producer == null)
 				throw new InvalidOperationException("BuildUnit without suitable production structure!");
 
-			var unit = new Actor(name, (1/24f * producer.CenterLocation).ToInt2(), player);
-			var mobile = unit.traits.Get<Mobile>();
-			mobile.facing = 128;
+			var unit = new Actor(name, (1/24f * producer.CenterLocation).ToInt2(), player);
+			var mobile = unit.traits.Get<Mobile>();
+			mobile.facing = 128;
 			mobile.QueueAction( new Traits.Mobile.MoveTo( unit.Location + new int2( 0, 3 ) ) );
 
 			world.AddFrameEndTask(_ => world.Add(unit));
 
 			// todo: make the producing building play `build`
+			if (producer.traits.Contains<RenderWarFactory>())
+				producer.traits.Get<RenderWarFactory>().EjectUnit();
 		}
 	}
 }
diff --git a/OpenRa.Game/Graphics/Animation.cs b/OpenRa.Game/Graphics/Animation.cs
index b7fd3d913c..00fa963dc2 100644
--- a/OpenRa.Game/Graphics/Animation.cs
+++ b/OpenRa.Game/Graphics/Animation.cs
@@ -7,6 +7,7 @@ namespace OpenRa.Game.Graphics
 		readonly string name;
 		Sequence currentSequence;
 		int frame = 0;
+		bool backwards = false;
 		bool tickAlways;
 
 		public Animation( string name )
@@ -15,7 +16,16 @@ namespace OpenRa.Game.Graphics
 			Play( "idle" );
 		}
 
-		public Sprite Image { get { return currentSequence.GetSprite( frame ); } }
+		public Sprite Image
+		{
+			get
+			{
+				return backwards
+					? currentSequence.GetSprite(currentSequence.End - frame - 1)
+					: currentSequence.GetSprite(frame);
+			}
+		}
+
 		public float2 Center { get { return 0.25f * new float2(currentSequence.GetSprite(0).bounds.Size); } }
 
 		public void Play( string sequenceName )
@@ -23,6 +33,11 @@ namespace OpenRa.Game.Graphics
 			PlayThen(sequenceName, () => { });
 		}
 
+		public void PlayBackwards(string sequenceName)
+		{
+			PlayBackwardsThen(sequenceName, () => { });
+		}
+
 		public void PlayRepeating( string sequenceName )
 		{
 			PlayThen( sequenceName, () => PlayRepeating( sequenceName ) );
@@ -30,6 +45,7 @@ namespace OpenRa.Game.Graphics
 
 		public void PlayThen( string sequenceName, Action after )
 		{
+			backwards = false;
 			tickAlways = false;
 			currentSequence = SequenceProvider.GetSequence( name, sequenceName );
 			frame = 0;
@@ -45,8 +61,15 @@ namespace OpenRa.Game.Graphics
 			};
 		}
 
+		public void PlayBackwardsThen(string sequenceName, Action after)
+		{
+			PlayThen(sequenceName, after);
+			backwards = true;
+		}
+
 		public void PlayFetchIndex( string sequenceName, Func<int> func )
 		{
+			backwards = false;
 			tickAlways = true;
 			currentSequence = SequenceProvider.GetSequence( name, sequenceName );
 			frame = func();
diff --git a/OpenRa.Game/Graphics/WorldRenderer.cs b/OpenRa.Game/Graphics/WorldRenderer.cs
index 0bc924cc22..abbc26f950 100644
--- a/OpenRa.Game/Graphics/WorldRenderer.cs
+++ b/OpenRa.Game/Graphics/WorldRenderer.cs
@@ -44,8 +44,8 @@ namespace OpenRa.Game.Graphics
 				spriteRenderer.DrawSprite(image.First, loc, 
 					(owner != null) ? owner.Palette : 0);
 			}
-		}
-
+		}
+
 		public void Draw()
 		{
 			var rect = new RectangleF((region.Position + Game.viewport.Location).ToPointF(), 
@@ -54,6 +54,11 @@ namespace OpenRa.Game.Graphics
 			foreach (Actor a in Game.world.Actors.OrderBy( u => u.CenterLocation.Y ))
 				DrawSpriteList(a.Owner, rect, a.Render());
 
+			foreach (var a in Game.world.Actors
+				.Where(u => u.traits.Contains<Traits.RenderWarFactory>())
+				.Select(u => u.traits.Get<Traits.RenderWarFactory>()))
+				DrawSpriteList(a.self.Owner, rect, a.RenderRoof(a.self));		/* RUDE HACK */
+
 			foreach (IEffect e in Game.world.Effects)
 				DrawSpriteList(e.Owner, rect, e.Render());
 
diff --git a/OpenRa.Game/Traits/RenderBuildingWarFactory.cs b/OpenRa.Game/Traits/RenderBuildingWarFactory.cs
index e68a2ddc17..c4b13a8a3f 100644
--- a/OpenRa.Game/Traits/RenderBuildingWarFactory.cs
+++ b/OpenRa.Game/Traits/RenderBuildingWarFactory.cs
@@ -11,10 +11,14 @@ namespace OpenRa.Game.Traits
 	{
 		public Animation roof;
 		bool doneBuilding;
+		bool isOpen;
+		public readonly Actor self;
 
 		public RenderWarFactory(Actor self)
 			: base(self)
 		{
+			this.self = self;
+
 			roof = new Animation(self.unitInfo.Image ?? self.unitInfo.Name);
 			anim.PlayThen("make", () =>
 			{
@@ -24,19 +28,32 @@ namespace OpenRa.Game.Traits
 			});
 		}
 
-		public override IEnumerable<Pair<Sprite, float2>> Render(Actor self)
+		public IEnumerable<Pair<Sprite, float2>> RenderRoof(Actor self)
 		{
 			if (doneBuilding)
-				return base.Render(self).Concat(
-					new[] { Pair.New(roof.Image, 24f * (float2)self.Location) });
-			else
-				return base.Render(self);
+				yield return Pair.New(roof.Image, 24f * (float2)self.Location);
 		}
 
 		public override void Tick(Actor self)
 		{
 			base.Tick(self);
 			roof.Tick();
+
+			var b = self.Bounds;
+			if (isOpen && !Game.SelectUnitsInBox(
+				new float2(b.Left, b.Top),
+				new float2(b.Right, b.Bottom)).Any(a => a.traits.Contains<Mobile>()))
+			{
+				isOpen = false;
+				roof.PlayBackwardsThen("build-top", () => roof.Play("idle-top"));
+			}
+		}
+
+		public void EjectUnit()
+		{
+			/* todo: hold the door open */
+
+			roof.PlayThen("build-top", () => isOpen = true);
 		}
 	}
 }