diff --git a/OpenRA.Mods.Cnc/FileFormats/WsaVideo.cs b/OpenRA.Mods.Cnc/FileFormats/WsaVideo.cs
index 495ea94950..d4cae79ec7 100644
--- a/OpenRA.Mods.Cnc/FileFormats/WsaVideo.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/WsaVideo.cs
@@ -120,7 +120,7 @@ namespace OpenRA.Mods.Cnc.FileFormats
 
 			var dataLength = frameOffsets[CurrentFrameIndex + 1] - frameOffsets[CurrentFrameIndex];
 
-			var rawData = StreamExts.ReadBytes(stream, (int)dataLength);
+			var rawData = stream.ReadBytes((int)dataLength);
 			var intermediateData = new byte[Width * Height];
 
 			// Format80 decompression
diff --git a/OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs b/OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs
index 19c5a4a3d2..6c0637bb8d 100644
--- a/OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs
+++ b/OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs
@@ -55,7 +55,7 @@ namespace OpenRA.Mods.Cnc.VideoLoaders
 
 			if (flags == 1)
 			{
-				var palette = StreamExts.ReadBytes(s, 768);
+				var palette = s.ReadBytes(768);
 				for (var i = 0; i < offsets.Length; i++)
 					offsets[i] += 768;
 			}
diff --git a/OpenRA.Mods.Common/Activities/Move/Move.cs b/OpenRA.Mods.Common/Activities/Move/Move.cs
index f1720b810b..812e77c050 100644
--- a/OpenRA.Mods.Common/Activities/Move/Move.cs
+++ b/OpenRA.Mods.Common/Activities/Move/Move.cs
@@ -204,7 +204,7 @@ namespace OpenRA.Mods.Common.Activities
 				return null;
 			}
 
-			var containsTemporaryBlocker = WorldUtils.ContainsTemporaryBlocker(self.World, nextCell, self);
+			var containsTemporaryBlocker = self.World.ContainsTemporaryBlocker(nextCell, self);
 
 			// Next cell in the move is blocked by another actor
 			if (containsTemporaryBlocker || !mobile.CanEnterCell(nextCell, ignoreActor))
diff --git a/OpenRA.Mods.Common/Effects/Beacon.cs b/OpenRA.Mods.Common/Effects/Beacon.cs
index 03521d0330..550855f70a 100644
--- a/OpenRA.Mods.Common/Effects/Beacon.cs
+++ b/OpenRA.Mods.Common/Effects/Beacon.cs
@@ -78,7 +78,7 @@ namespace OpenRA.Mods.Common.Effects
 				if (clockFraction != null)
 				{
 					clock = new Animation(owner.World, posterCollection);
-					clock.PlayFetchIndex(clockSequence, () => Exts.Clamp((int)(clockFraction() * (clock.CurrentSequence.Length - 1)), 0, clock.CurrentSequence.Length - 1));
+					clock.PlayFetchIndex(clockSequence, () => ((int)(clockFraction() * (clock.CurrentSequence.Length - 1))).Clamp(0, clock.CurrentSequence.Length - 1));
 				}
 			}
 		}
diff --git a/OpenRA.Mods.Common/Orders/GlobalButtonOrderGenerator.cs b/OpenRA.Mods.Common/Orders/GlobalButtonOrderGenerator.cs
index d76c573a77..c8ce76e2f2 100644
--- a/OpenRA.Mods.Common/Orders/GlobalButtonOrderGenerator.cs
+++ b/OpenRA.Mods.Common/Orders/GlobalButtonOrderGenerator.cs
@@ -35,7 +35,7 @@ namespace OpenRA.Mods.Common.Orders
 
 		protected virtual bool IsValidTrait(T t)
 		{
-			return Exts.IsTraitEnabled(t);
+			return t.IsTraitEnabled();
 		}
 
 		protected IEnumerable<Order> OrderInner(World world, MouseInput mi)
diff --git a/OpenRA.Mods.Common/Traits/BlocksProjectiles.cs b/OpenRA.Mods.Common/Traits/BlocksProjectiles.cs
index 1a76783553..c6a0e6f7b4 100644
--- a/OpenRA.Mods.Common/Traits/BlocksProjectiles.cs
+++ b/OpenRA.Mods.Common/Traits/BlocksProjectiles.cs
@@ -58,7 +58,7 @@ namespace OpenRA.Mods.Common.Traits
 				if (blockers.Count == 0)
 					continue;
 
-				var hitPos = WorldExtensions.MinimumPointLineProjection(start, end, a.CenterPosition);
+				var hitPos = start.MinimumPointLineProjection(end, a.CenterPosition);
 				var dat = world.Map.DistanceAboveTerrain(hitPos);
 				if ((hitPos - start).Length < length && blockers.Any(t => t.BlockingHeight > dat))
 				{
diff --git a/OpenRA.Mods.Common/UtilityCommands/ExtractWeaponDocsCommand.cs b/OpenRA.Mods.Common/UtilityCommands/ExtractWeaponDocsCommand.cs
index 6364d0f584..2312e94337 100644
--- a/OpenRA.Mods.Common/UtilityCommands/ExtractWeaponDocsCommand.cs
+++ b/OpenRA.Mods.Common/UtilityCommands/ExtractWeaponDocsCommand.cs
@@ -52,7 +52,7 @@ namespace OpenRA.Mods.Common.UtilityCommands
 			var warheads = objectCreator.GetTypesImplementing<IWarhead>().OrderBy(t => t.Namespace);
 			var projectiles = objectCreator.GetTypesImplementing<IProjectileInfo>().OrderBy(t => t.Namespace);
 
-			var weaponTypes = Enumerable.Concat(weaponInfo, Enumerable.Concat(projectiles, warheads));
+			var weaponTypes = weaponInfo.Concat(projectiles.Concat(warheads));
 			foreach (var t in weaponTypes)
 			{
 				// skip helpers like TraitInfo<T>
diff --git a/OpenRA.Mods.Common/WorldExtensions.cs b/OpenRA.Mods.Common/WorldExtensions.cs
index 8f9fee53d0..48e1e45aa8 100644
--- a/OpenRA.Mods.Common/WorldExtensions.cs
+++ b/OpenRA.Mods.Common/WorldExtensions.cs
@@ -53,7 +53,7 @@ namespace OpenRA.Mods.Common
 				if (shapes.Any())
 					actorWidth = shapes.Max(h => h.Info.Type.OuterRadius.Length);
 
-				var projection = MinimumPointLineProjection(lineStart, lineEnd, currActor.CenterPosition);
+				var projection = lineStart.MinimumPointLineProjection(lineEnd, currActor.CenterPosition);
 				var distance = (currActor.CenterPosition - projection).HorizontalLength;
 				var maxReach = actorWidth + lineWidth.Length;
 
@@ -84,7 +84,7 @@ namespace OpenRA.Mods.Common
 		/// <param name="lineEnd">The target point (head) of the line</param>
 		/// <param name="point">The target point that the minimum distance should be found to</param>
 		/// <returns>The WPos that is the point on the line that is closest to the target point</returns>
-		public static WPos MinimumPointLineProjection(WPos lineStart, WPos lineEnd, WPos point)
+		public static WPos MinimumPointLineProjection(this WPos lineStart, WPos lineEnd, WPos point)
 		{
 			var squaredLength = (lineEnd - lineStart).HorizontalLengthSquared;