diff --git a/OpenRA.Game/OpenRA.Game.csproj b/OpenRA.Game/OpenRA.Game.csproj
index 09495ea5da..6d8eda9288 100644
--- a/OpenRA.Game/OpenRA.Game.csproj
+++ b/OpenRA.Game/OpenRA.Game.csproj
@@ -227,7 +227,6 @@
     <Compile Include="Graphics\IGraphicsDevice.cs" />
     <Compile Include="Sound\Sound.cs" />
     <Compile Include="Sound\SoundDevice.cs" />
-    <Compile Include="Effects\SpriteEffect.cs" />
     <Compile Include="Graphics\SelectionBarsRenderable.cs" />
     <Compile Include="Graphics\TargetLineRenderable.cs" />
     <Compile Include="Graphics\UISpriteRenderable.cs" />
@@ -241,7 +240,6 @@
     <Compile Include="Widgets\WidgetLoader.cs" />
     <Compile Include="Widgets\ChromeMetrics.cs" />
     <Compile Include="Widgets\WidgetUtils.cs" />
-    <Compile Include="Widgets\WorldInteractionControllerWidget.cs" />
     <Compile Include="Graphics\PaletteReference.cs" />
     <Compile Include="Graphics\TerrainSpriteLayer.cs" />
     <Compile Include="Map\ProjectedCellRegion.cs" />
diff --git a/OpenRA.Game/Effects/SpriteEffect.cs b/OpenRA.Mods.Common/Effects/SpriteEffect.cs
similarity index 96%
rename from OpenRA.Game/Effects/SpriteEffect.cs
rename to OpenRA.Mods.Common/Effects/SpriteEffect.cs
index 1976de8012..a6022d40d2 100644
--- a/OpenRA.Game/Effects/SpriteEffect.cs
+++ b/OpenRA.Mods.Common/Effects/SpriteEffect.cs
@@ -10,9 +10,10 @@
 #endregion
 
 using System.Collections.Generic;
+using OpenRA.Effects;
 using OpenRA.Graphics;
 
-namespace OpenRA.Effects
+namespace OpenRA.Mods.Common.Effects
 {
 	public class SpriteEffect : IEffect
 	{
diff --git a/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj b/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
index 0f83ca0cfc..2e20f66a60 100644
--- a/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
+++ b/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
@@ -163,6 +163,7 @@
     <Compile Include="Effects\RallyPointIndicator.cs" />
     <Compile Include="Effects\RepairIndicator.cs" />
     <Compile Include="Effects\Smoke.cs" />
+    <Compile Include="Effects\SpriteEffect.cs" />
     <Compile Include="Commands\ChatCommands.cs" />
     <Compile Include="Commands\DevCommands.cs" />
     <Compile Include="Commands\HelpCommand.cs" />
@@ -646,6 +647,7 @@
     <Compile Include="Widgets\SupportPowerTimerWidget.cs" />
     <Compile Include="Widgets\TerrainTemplatePreviewWidget.cs" />
     <Compile Include="Widgets\WorldCommandWidget.cs" />
+    <Compile Include="Widgets\WorldInteractionControllerWidget.cs" />
     <Compile Include="SpriteLoaders\ShpTDLoader.cs" />
     <Compile Include="SpriteLoaders\ShpTSLoader.cs" />
     <Compile Include="SpriteLoaders\TmpRALoader.cs" />
diff --git a/OpenRA.Mods.Common/Traits/Render/LeavesTrails.cs b/OpenRA.Mods.Common/Traits/Render/LeavesTrails.cs
index f8f85ca5eb..c8e68afad0 100644
--- a/OpenRA.Mods.Common/Traits/Render/LeavesTrails.cs
+++ b/OpenRA.Mods.Common/Traits/Render/LeavesTrails.cs
@@ -10,7 +10,7 @@
 #endregion
 
 using System.Collections.Generic;
-using OpenRA.Effects;
+using OpenRA.Mods.Common.Effects;
 using OpenRA.Traits;
 
 namespace OpenRA.Mods.Common.Traits.Render
diff --git a/OpenRA.Mods.Common/Traits/SupportPowers/SpawnActorPower.cs b/OpenRA.Mods.Common/Traits/SupportPowers/SpawnActorPower.cs
index 3fc52122f3..323c950f5e 100644
--- a/OpenRA.Mods.Common/Traits/SupportPowers/SpawnActorPower.cs
+++ b/OpenRA.Mods.Common/Traits/SupportPowers/SpawnActorPower.cs
@@ -9,8 +9,8 @@
  */
 #endregion
 
-using OpenRA.Effects;
 using OpenRA.Mods.Common.Activities;
+using OpenRA.Mods.Common.Effects;
 using OpenRA.Primitives;
 using OpenRA.Traits;
 
diff --git a/OpenRA.Game/Widgets/WorldInteractionControllerWidget.cs b/OpenRA.Mods.Common/Widgets/WorldInteractionControllerWidget.cs
similarity index 99%
rename from OpenRA.Game/Widgets/WorldInteractionControllerWidget.cs
rename to OpenRA.Mods.Common/Widgets/WorldInteractionControllerWidget.cs
index 386033902e..5e4c0e913f 100644
--- a/OpenRA.Game/Widgets/WorldInteractionControllerWidget.cs
+++ b/OpenRA.Mods.Common/Widgets/WorldInteractionControllerWidget.cs
@@ -14,10 +14,12 @@ using System.Drawing;
 using System.Linq;
 using OpenRA.Effects;
 using OpenRA.Graphics;
+using OpenRA.Mods.Common.Effects;
 using OpenRA.Orders;
 using OpenRA.Traits;
+using OpenRA.Widgets;
 
-namespace OpenRA.Widgets
+namespace OpenRA.Mods.Common.Widgets
 {
 	public class WorldInteractionControllerWidget : Widget
 	{