diff --git a/OpenRA.Game/Chrome.cs b/OpenRA.Game/Chrome.cs
index 41d313cece..530ba350b5 100644
--- a/OpenRA.Game/Chrome.cs
+++ b/OpenRA.Game/Chrome.cs
@@ -341,7 +341,7 @@ namespace OpenRA
 				new int2(mapRect.Left + mapRect.Width / 2, y), Color.White);
 			y += 20;
 			
-			TheaterInfo theaterInfo = Game.world.WorldActor.Info.Traits.WithInterface<TheaterInfo>().Where(t => t.Theater == currentMap.Map.Theater).FirstOrDefault();
+			var theaterInfo = Game.world.WorldActor.Info.Traits.WithInterface<TheaterInfo>().FirstOrDefault(t => t.Theater == currentMap.Map.Theater);
 			DrawCentered("Theater: {0}".F(theaterInfo.Name, currentMap.Map.Height),
 				new int2(mapRect.Left + mapRect.Width / 2, y), Color.White);
 			y += 20;
diff --git a/OpenRA.Game/World.cs b/OpenRA.Game/World.cs
index 9e23c58330..3adca8c670 100644
--- a/OpenRA.Game/World.cs
+++ b/OpenRA.Game/World.cs
@@ -79,7 +79,7 @@ namespace OpenRA
 			customTerrain = new ICustomTerrain[Map.MapSize, Map.MapSize];
 			Timer.Time( "new Map: {0}" );
 			
-			TheaterInfo theaterInfo = Rules.Info["world"].Traits.WithInterface<TheaterInfo>().Where(t => t.Theater == Map.Theater).FirstOrDefault();
+			var theaterInfo = Rules.Info["world"].Traits.WithInterface<TheaterInfo>().FirstOrDefault(t => t.Theater == Map.Theater);
 			TileSet = new TileSet(theaterInfo.Tileset, theaterInfo.Templates, theaterInfo.Suffix);
 			
 			SpriteSheetBuilder.Initialize( Map );
diff --git a/mods/ra/rules.yaml b/mods/ra/rules.yaml
index a405bd3085..3227495bdb 100644
--- a/mods/ra/rules.yaml
+++ b/mods/ra/rules.yaml
@@ -256,6 +256,12 @@ World:
 		Suffix:tem
 		Templates:templates.ini
 		Tileset:tileSet.til
+	Theater@INTERIOR:
+		Name:Interior
+		Theater:INTERIOR
+		Suffix:int
+		Templates:templates.ini
+		Tileset:tileSet.til
 
 MGG:
 	GeneratesGap: