diff --git a/BizHawk.Client.Common/RecentFiles.cs b/BizHawk.Client.Common/RecentFiles.cs
index ebf6447744..1ecedee4a1 100644
--- a/BizHawk.Client.Common/RecentFiles.cs
+++ b/BizHawk.Client.Common/RecentFiles.cs
@@ -90,7 +90,7 @@ namespace BizHawk.Client.Common
 			if (!Frozen)
 			{
 				var removed = false;
-				foreach (var recent in recentlist.ToList())
+				foreach (var recent in recentlist)
 				{
 					if (string.Compare(newFile, recent, StringComparison.CurrentCultureIgnoreCase) == 0)
 					{
diff --git a/BizHawk.Client.Common/config/PathEntry.cs b/BizHawk.Client.Common/config/PathEntry.cs
index 9b6b710212..aa345690bd 100644
--- a/BizHawk.Client.Common/config/PathEntry.cs
+++ b/BizHawk.Client.Common/config/PathEntry.cs
@@ -119,8 +119,7 @@ namespace BizHawk.Client.Common
 			}
 
 			// Add missing displaynames
-			var missingDisplayPaths = Paths.Where(p => p.SystemDisplayName == null).ToList();
-			foreach (PathEntry path in missingDisplayPaths)
+			foreach (var path in Paths.Where(p => p.SystemDisplayName == null))
 			{
 				path.SystemDisplayName = DefaultValues.First(p => p.System == path.System).SystemDisplayName;
 			}
diff --git a/BizHawk.Client.EmuHawk/BizBox.cs b/BizHawk.Client.EmuHawk/BizBox.cs
index 14da9178bf..5f9e509e82 100644
--- a/BizHawk.Client.EmuHawk/BizBox.cs
+++ b/BizHawk.Client.EmuHawk/BizBox.cs
@@ -41,17 +41,12 @@ namespace BizHawk.Client.EmuHawk
 			VersionLabel.Text = "Version " + mainversion;
 			DateLabel.Text = VersionInfo.RELEASEDATE;
 
-			var cores = Assembly
-				.Load("BizHawk.Emulation.Cores")
-				.GetTypes()
+			foreach (var core in Assembly.Load("BizHawk.Emulation.Cores").GetTypes()
 				.Where(t => typeof(IEmulator).IsAssignableFrom(t))
 				.Select(t => t.GetCustomAttributes(false).OfType<CoreAttribute>().FirstOrDefault())
 				.Where(a => a != null)
 				.Where(a => a.Released)
-				.OrderByDescending(a => a.CoreName.ToLower())
-				.ToList();
-
-			foreach (var core in cores)
+				.OrderByDescending(a => a.CoreName.ToLower()))
 			{
 				CoreInfoPanel.Controls.Add(new BizBoxInfoControl(core)
 				{
diff --git a/BizHawk.Client.EmuHawk/CustomControls/InputRoll.cs b/BizHawk.Client.EmuHawk/CustomControls/InputRoll.cs
index 3226c99e94..96ef08562f 100644
--- a/BizHawk.Client.EmuHawk/CustomControls/InputRoll.cs
+++ b/BizHawk.Client.EmuHawk/CustomControls/InputRoll.cs
@@ -1374,7 +1374,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (SelectedRows.Any() && LetKeysModifySelection && SelectedRows.First() > 0)
 					{
-						foreach (var row in SelectedRows.ToList())
+						foreach (var row in SelectedRows)
 						{
 							SelectRow(row - 1, true);
 							SelectRow(row, false);
@@ -1385,7 +1385,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (SelectedRows.Any() && LetKeysModifySelection)
 					{
-						foreach (var row in SelectedRows.Reverse().ToList())
+						foreach (var row in SelectedRows.Reverse())
 						{
 							SelectRow(row + 1, true);
 							SelectRow(row, false);
diff --git a/BizHawk.Client.EmuHawk/MainForm.Hotkey.cs b/BizHawk.Client.EmuHawk/MainForm.Hotkey.cs
index 7732f31930..a64a24e3db 100644
--- a/BizHawk.Client.EmuHawk/MainForm.Hotkey.cs
+++ b/BizHawk.Client.EmuHawk/MainForm.Hotkey.cs
@@ -347,7 +347,7 @@ namespace BizHawk.Client.EmuHawk
 							type = " (on)";
 						}
 
-						Global.CheatList.ToList().ForEach(x => x.Toggle());
+						foreach (var x in Global.CheatList) x.Toggle();
 						GlobalWin.OSD.AddMessage("Cheats toggled" + type);
 					}
 
diff --git a/BizHawk.Client.EmuHawk/Sound/Output/DirectSoundSoundOutput.cs b/BizHawk.Client.EmuHawk/Sound/Output/DirectSoundSoundOutput.cs
index df362aa7aa..8a3045e516 100644
--- a/BizHawk.Client.EmuHawk/Sound/Output/DirectSoundSoundOutput.cs
+++ b/BizHawk.Client.EmuHawk/Sound/Output/DirectSoundSoundOutput.cs
@@ -43,7 +43,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public static IEnumerable<string> GetDeviceNames()
 		{
-			return DirectSound.GetDevices().Select(d => d.Description).ToList();
+			return DirectSound.GetDevices().Select(d => d.Description);
 		}
 
 		private int BufferSizeSamples { get; set; }
diff --git a/BizHawk.Client.EmuHawk/Sound/Output/XAudio2SoundOutput.cs b/BizHawk.Client.EmuHawk/Sound/Output/XAudio2SoundOutput.cs
index 913fb91c94..1fe3510921 100644
--- a/BizHawk.Client.EmuHawk/Sound/Output/XAudio2SoundOutput.cs
+++ b/BizHawk.Client.EmuHawk/Sound/Output/XAudio2SoundOutput.cs
@@ -50,7 +50,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			using (XAudio2 device = new XAudio2())
 			{
-				return Enumerable.Range(0, device.DeviceCount).Select(n => device.GetDeviceDetails(n).DisplayName).ToList();
+				return Enumerable.Range(0, device.DeviceCount).Select(n => device.GetDeviceDetails(n).DisplayName);
 			}
 		}
 
diff --git a/BizHawk.Client.EmuHawk/config/HotkeyConfig.cs b/BizHawk.Client.EmuHawk/config/HotkeyConfig.cs
index 24adc44d21..e29f028f5d 100644
--- a/BizHawk.Client.EmuHawk/config/HotkeyConfig.cs
+++ b/BizHawk.Client.EmuHawk/config/HotkeyConfig.cs
@@ -101,21 +101,20 @@ namespace BizHawk.Client.EmuHawk
 			HotkeyTabControl.TabPages.Clear();
 
 			// Buckets
-			var tabs = Global.Config.HotkeyBindings.Select(x => x.TabGroup).Distinct().ToList();
 
-			foreach (var tab in tabs)
+			foreach (var tab in Global.Config.HotkeyBindings.Select(x => x.TabGroup).Distinct())
 			{
 				var _y = UIHelper.ScaleY(14);
 				var _x = UIHelper.ScaleX(6);
 
 				var tb = new TabPage {Name = tab, Text = tab};
 
-				var bindings = Global.Config.HotkeyBindings.Where(x => x.TabGroup == tab).OrderBy(x => x.Ordinal).ThenBy(x => x.DisplayName).ToList();
-
 				int iwOffsetX = UIHelper.ScaleX(110);
 				int iwOffsetY = UIHelper.ScaleY(-4);
 				int iwWidth = UIHelper.ScaleX(120);
-				foreach (var b in bindings)
+				foreach (var b in Global.Config.HotkeyBindings.Where(x => x.TabGroup == tab)
+					.OrderBy(x => x.Ordinal)
+					.ThenBy(x => x.DisplayName))
 				{
 					var l = new Label
 					{
diff --git a/BizHawk.Client.EmuHawk/config/NES/NESSyncSettingsForm.cs b/BizHawk.Client.EmuHawk/config/NES/NESSyncSettingsForm.cs
index a8aeb3d815..cc14be63fc 100644
--- a/BizHawk.Client.EmuHawk/config/NES/NESSyncSettingsForm.cs
+++ b/BizHawk.Client.EmuHawk/config/NES/NESSyncSettingsForm.cs
@@ -64,7 +64,7 @@ namespace BizHawk.Client.EmuHawk
 				typeof(NES.NESSyncSettings.Region),
 				(string)RegionComboBox.SelectedItem);
 
-			List<byte> oldRam = _syncSettings.InitialWRamStatePattern?.ToList() ?? new List<byte>();
+			var oldRam = _syncSettings.InitialWRamStatePattern ?? Enumerable.Empty<byte>();
 
 			if (!string.IsNullOrWhiteSpace(RamPatternOverrideBox.Text))
 			{
diff --git a/BizHawk.Client.EmuHawk/config/PathConfig.cs b/BizHawk.Client.EmuHawk/config/PathConfig.cs
index 6c7ef17e6b..16198f7b72 100644
--- a/BizHawk.Client.EmuHawk/config/PathConfig.cs
+++ b/BizHawk.Client.EmuHawk/config/PathConfig.cs
@@ -111,14 +111,11 @@ namespace BizHawk.Client.EmuHawk
 					Width = UIHelper.ScaleX(200), // Initial Left/Width of child controls are based on this size.
 					AutoScroll = true
 				};
-				var paths = pathCollection
-					.Where(p => p.System == systemId)
-					.OrderBy(p => p.Ordinal)
-					.ThenBy(p => p.Type)
-					.ToList();
 
 				var y = UIHelper.ScaleY(14);
-				foreach (var path in paths)
+				foreach (var path in pathCollection.Where(p => p.System == systemId)
+					.OrderBy(p => p.Ordinal)
+					.ThenBy(p => p.Type))
 				{
 					var box = new TextBox
 					{
@@ -243,10 +240,8 @@ namespace BizHawk.Client.EmuHawk
 
 		private void DoRomToggle()
 		{
-			AllPathControls
-				.Where(c => c.Name == "ROM")
-				.ToList()
-				.ForEach(control => control.Enabled = !RecentForROMs.Checked);
+			foreach (var control in AllPathControls.Where(c => c.Name == "ROM"))
+				control.Enabled = !RecentForROMs.Checked;
 		}
 
 		private IEnumerable<TextBox> AllPathBoxes
diff --git a/BizHawk.Client.EmuHawk/movie/PlayMovie.cs b/BizHawk.Client.EmuHawk/movie/PlayMovie.cs
index 058a873c90..c223f39631 100644
--- a/BizHawk.Client.EmuHawk/movie/PlayMovie.cs
+++ b/BizHawk.Client.EmuHawk/movie/PlayMovie.cs
@@ -306,13 +306,9 @@ namespace BizHawk.Client.EmuHawk
 
 		private void MovieView_DragDrop(object sender, DragEventArgs e)
 		{
-			var filePaths = (string[])e.Data.GetData(DataFormats.FileDrop);
-
-			filePaths
-				.Where(path => MovieService.MovieExtensions.Contains(Path.GetExtension(path).Replace(".", "")))
-				.ToList()
-				.ForEach(path => AddMovieToList(path, force: true));
-
+			foreach (var path in ((string[])e.Data.GetData(DataFormats.FileDrop))
+				.Where(path => MovieService.MovieExtensions.Contains(Path.GetExtension(path)?.Replace(".", ""))))
+					AddMovieToList(path, force: true);
 			RefreshMovieList();
 		}
 
@@ -470,11 +466,8 @@ namespace BizHawk.Client.EmuHawk
 
 		private void EditMenuItem_Click(object sender, EventArgs e)
 		{
-			MovieView.SelectedIndices
-				.Cast<int>()
-				.SelectAsIndexOf(_movieList)
-				.ToList()
-				.ForEach(movie => System.Diagnostics.Process.Start(movie.Filename));
+			foreach (var movie in MovieView.SelectedIndices.Cast<int>().SelectAsIndexOf(_movieList))
+				System.Diagnostics.Process.Start(movie.Filename);
 		}
 
 		#endregion
diff --git a/BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs b/BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs
index 5c3e484926..8048967d84 100644
--- a/BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs
+++ b/BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs
@@ -438,10 +438,8 @@ namespace BizHawk.Client.EmuHawk
 			CurrentFileName = "";
 			_bestBotAttempt = null;
 
-			ControlProbabilityPanel.Controls
-				.OfType<BotControlsRow>()
-				.ToList()
-				.ForEach(cp => cp.Probability = 0);
+			foreach (var cp in ControlProbabilityPanel.Controls.OfType<BotControlsRow>())
+				cp.Probability = 0;
 
 			FrameLength = 0;
 			MaximizeAddress = 0;
diff --git a/BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs b/BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs
index f1a35cc63c..ee703f3e2a 100644
--- a/BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs
+++ b/BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs
@@ -478,13 +478,8 @@ namespace BizHawk.Client.EmuHawk
 				Global.CheatList.Insert(index - 1, cheat);
 			}
 
-			var newindices = indices.Select(t => t - 1).ToList();
-
 			CheatListView.SelectedIndices.Clear();
-			foreach (var newi in newindices)
-			{
-				CheatListView.SelectItem(newi, true);
-			}
+			foreach (var index in indices) CheatListView.SelectItem(index - 1, true);
 
 			UpdateMessageLabel();
 			UpdateDialog();
@@ -507,13 +502,8 @@ namespace BizHawk.Client.EmuHawk
 
 			UpdateMessageLabel();
 
-			var newindices = indices.Select(t => t + 1).ToList();
-
 			CheatListView.SelectedIndices.Clear();
-			foreach (var newi in newindices)
-			{
-				CheatListView.SelectItem(newi, true);
-			}
+			foreach (var index in indices) CheatListView.SelectItem(index + 1, true);
 
 			UpdateDialog();
 		}
@@ -525,7 +515,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void ToggleMenuItem_Click(object sender, EventArgs e)
 		{
-			SelectedCheats.ToList().ForEach(x => x.Toggle());
+			foreach (var x in SelectedCheats) x.Toggle();
 			CheatListView.Refresh();
 		}
 
diff --git a/BizHawk.Client.EmuHawk/tools/Debugger/RegisterBoxControl.cs b/BizHawk.Client.EmuHawk/tools/Debugger/RegisterBoxControl.cs
index 9f6d273e8f..51ef188277 100644
--- a/BizHawk.Client.EmuHawk/tools/Debugger/RegisterBoxControl.cs
+++ b/BizHawk.Client.EmuHawk/tools/Debugger/RegisterBoxControl.cs
@@ -41,46 +41,40 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (Controls.OfType<Panel>().Any(p => p.Name == "FlagPanel"))
 					{
-						Controls
+						foreach (var checkbox in Controls
 							.OfType<Panel>()
 							.First(p => p.Name == "FlagPanel")
 							.Controls
-							.OfType<CheckBox>()
-							.ToList()
-							.ForEach(checkbox =>
+							.OfType<CheckBox>())
+						{
+							if (checkbox.Name == register.Key)
 							{
-								if (checkbox.Name == register.Key)
-								{
-									checkbox.Checked = register.Value.Value == 1;
-								}
-							});
+								checkbox.Checked = register.Value.Value == 1;
+							}
+						}
 					}
 
 					if (_canSetCpuRegisters)
 					{
-						Controls
-							.OfType<TextBox>()
-							.ToList()
-							.ForEach(textbox =>
+						foreach (var textbox in Controls
+							.OfType<TextBox>())
+						{
+							if (textbox.Name == register.Key)
 							{
-								if (textbox.Name == register.Key)
-								{
-									textbox.Text = register.Value.Value.ToHexString(register.Value.BitSize / 4);
-								}
-							});
+								textbox.Text = register.Value.Value.ToHexString(register.Value.BitSize / 4);
+							}
+						}
 					}
 					else
 					{
-						Controls
-							.OfType<Label>()
-							.ToList()
-							.ForEach(label =>
+						foreach (var label in Controls
+							.OfType<Label>())
+						{
+							if (label.Name == register.Key)
 							{
-								if (label.Name == register.Key)
-								{
-									label.Text = register.Value.Value.ToHexString(register.Value.BitSize / 4);
-								}
-							});
+								label.Text = register.Value.Value.ToHexString(register.Value.BitSize / 4);
+							}
+						}
 					}
 				}
 
diff --git a/BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs b/BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs
index 31e4f0386a..7edad5926e 100644
--- a/BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs
+++ b/BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs
@@ -213,7 +213,7 @@ namespace BizHawk.Client.EmuHawk
 				SetDomain(domain);
 				SetHighlighted(addrList[0]);
 				_secondaryHighlightedAddresses.Clear();
-				_secondaryHighlightedAddresses.AddRange(addrList.Where(addr => addr != addrList[0]).ToList());
+				_secondaryHighlightedAddresses.AddRange(addrList.Where(addr => addr != addrList[0]));
 				ClearNibbles();
 				UpdateValues();
 				MemoryViewerBox.Refresh();
@@ -837,8 +837,7 @@ namespace BizHawk.Client.EmuHawk
 			if (address >= 0) 
 			{
 				// TODO: can't unfreeze address 0??
-				Global.CheatList.RemoveRange(
-					Global.CheatList.Where(x => x.Contains(address)).ToList());
+				Global.CheatList.RemoveRange(Global.CheatList.Where(x => x.Contains(address)));
 			}
 
 			MemoryViewerBox.Refresh();
diff --git a/BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Forms.cs b/BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Forms.cs
index 3b94fbf40d..2c1e5cc08c 100644
--- a/BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Forms.cs
+++ b/BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Forms.cs
@@ -149,8 +149,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (control.Handle == ptr)
 					{
-						var luaEvents = form.ControlEvents.Where(x => x.Control == ptr).ToList();
-						foreach (var luaEvent in luaEvents)
+						foreach (var luaEvent in form.ControlEvents.Where(x => x.Control == ptr))
 						{
 							form.ControlEvents.Remove(luaEvent);
 						}
diff --git a/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs b/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs
index 04a6ead8e0..481b0861e0 100644
--- a/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs
+++ b/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs
@@ -701,7 +701,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private static void UpdateRegisteredFunctionsDialog()
 		{
-			foreach (var form in Application.OpenForms.OfType<LuaRegisteredFunctionsList>().ToList())
+			foreach (var form in Application.OpenForms.OfType<LuaRegisteredFunctionsList>())
 			{
 				form.UpdateValues();
 			}
@@ -919,7 +919,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void PauseScriptMenuItem_Click(object sender, EventArgs e)
 		{
-			SelectedFiles.ToList().ForEach(x => x.TogglePause());
+			foreach (var x in SelectedFiles) x.TogglePause();
 			UpdateDialog();
 		}
 
@@ -932,11 +932,11 @@ namespace BizHawk.Client.EmuHawk
 
 		private void EditScriptMenuItem_Click(object sender, EventArgs e)
 		{
-			SelectedFiles.ToList().ForEach(file =>
+			foreach (var file in SelectedFiles)
 			{
 				string pathToLoad = ProcessPath(file.Path);
 				System.Diagnostics.Process.Start(pathToLoad);
-			});
+			}
 		}
 
 		private void RemoveScriptMenuItem_Click(object sender, EventArgs e)
diff --git a/BizHawk.Client.EmuHawk/tools/Lua/LuaRegisteredFunctionsList.cs b/BizHawk.Client.EmuHawk/tools/Lua/LuaRegisteredFunctionsList.cs
index af887bab05..2849051a1c 100644
--- a/BizHawk.Client.EmuHawk/tools/Lua/LuaRegisteredFunctionsList.cs
+++ b/BizHawk.Client.EmuHawk/tools/Lua/LuaRegisteredFunctionsList.cs
@@ -45,9 +45,10 @@ namespace BizHawk.Client.EmuHawk
 		private void PopulateListView()
 		{
 			FunctionView.Items.Clear();
-			
-			var nlfs = GlobalWin.Tools.LuaConsole.LuaImp.GetRegisteredFunctions().OrderBy(x => x.Event).ThenBy(x => x.Name).ToList();
-			foreach (var nlf in nlfs)
+
+			foreach (var nlf in GlobalWin.Tools.LuaConsole.LuaImp.GetRegisteredFunctions()
+				.OrderBy(x => x.Event)
+				.ThenBy(x => x.Name))
 			{
 				var item = new ListViewItem { Text = nlf.Event };
 				item.SubItems.Add(nlf.Name);
diff --git a/BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskBundler.cs b/BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskBundler.cs
index 4ea575c4b2..b7c2c88e15 100644
--- a/BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskBundler.cs
+++ b/BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskBundler.cs
@@ -185,9 +185,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			try
 			{
-				var fileSelectors = FileSelectors.ToList();
-
-				var names = fileSelectors.Select(f => f.GetName());
+				var names = FileSelectors.Select(f => f.GetName());
 
 				var name = NameBox.Text;
 
diff --git a/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs b/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs
index 12d520eb49..79b01df7fb 100644
--- a/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs
+++ b/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs
@@ -677,13 +677,9 @@ namespace BizHawk.Client.EmuHawk
 			if (TasView.AnyRowsSelected)
 			{
 				var wasPaused = Mainform.EmulatorPaused;
-				var framesToInsert = TasView.SelectedRows.ToList();
 				var insertionFrame = Math.Min(TasView.LastSelectedIndex.Value + 1, CurrentTasMovie.InputLogLength);
 				var needsToRollback = TasView.FirstSelectedIndex < Emulator.Frame;
-
-				var inputLog = framesToInsert
-					.Select(frame => CurrentTasMovie.GetInputLogEntry(frame))
-					.ToList();
+				var inputLog = TasView.SelectedRows.Select(frame => CurrentTasMovie.GetInputLogEntry(frame)).ToList();
 
 				CurrentTasMovie.InsertInput(insertionFrame, inputLog);
 
@@ -780,8 +776,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void RemoveMarkersMenuItem_Click(object sender, EventArgs e)
 		{
-			IEnumerable<TasMovieMarker> markers = CurrentTasMovie.Markers.Where(m => TasView.SelectedRows.Contains(m.Frame));
-			foreach (TasMovieMarker m in markers.ToList())
+			foreach (var m in CurrentTasMovie.Markers.Where(m => TasView.SelectedRows.Contains(m.Frame)))
 			{
 				CurrentTasMovie.Markers.Remove(m);
 			}
diff --git a/BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualPad.cs b/BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualPad.cs
index 3c1a328662..7e0583e54c 100644
--- a/BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualPad.cs
+++ b/BizHawk.Client.EmuHawk/tools/VirtualPads/VirtualPad.cs
@@ -136,10 +136,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public void ClearBoolean()
 		{
-			PadControls
-				.OfType<VirtualPadButton>()
-				.ToList()
-				.ForEach(p => p.Clear());
+			foreach (var p in PadControls.OfType<VirtualPadButton>()) p.Clear();
 		}
 
 		public void Set(IController controller)
@@ -149,28 +146,14 @@ namespace BizHawk.Client.EmuHawk
 
 		public void SetPrevious(IController previous)
 		{
-			PadControls
-				.OfType<VirtualPadAnalogStick>()
-				.ToList()
-				.ForEach(c => c.SetPrevious(previous));
+			foreach (var c in PadControls.OfType<VirtualPadAnalogStick>()) c.SetPrevious(previous);
 		}
 
 		public void BumpAnalog(int? x, int? y)
 		{
-			PadControls
-				.OfType<VirtualPadAnalogStick>()
-				.ToList()
-				.ForEach(a => a.Bump(x, y));
-
-			PadControls
-				.OfType<VirtualPadAnalogButton>()
-				.ToList()
-				.ForEach(a => a.Bump(x));
-
-			PadControls
-				.OfType<VirtualPadTargetScreen>()
-				.ToList()
-				.ForEach(a => a.Bump(x, y));
+			foreach (var a in PadControls.OfType<VirtualPadAnalogStick>()) a.Bump(x, y);
+			foreach (var a in PadControls.OfType<VirtualPadAnalogButton>()) a.Bump(x);
+			foreach (var a in PadControls.OfType<VirtualPadTargetScreen>()) a.Bump(x, y);
 		}
 	}
 }
diff --git a/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs b/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
index e2def5df86..362e55d277 100644
--- a/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
+++ b/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
@@ -876,7 +876,7 @@ namespace BizHawk.Client.EmuHawk
 					InitialLocation = this.ChildPointToScreen(WatchListView)
 				};
 
-				poke.SetWatch(SelectedIndices.Select(t => _searches[t]).ToList());
+				poke.SetWatch(SelectedIndices.Select(t => _searches[t]));
 				poke.ShowHawkDialog();
 
 				UpdateList();
@@ -1512,10 +1512,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void ErrorIconButton_Click(object sender, EventArgs e)
 		{
-			var outOfRangeAddresses = _searches.OutOfRangeAddress.ToList();
-
-			SetRemovedMessage(outOfRangeAddresses.Count);
-
+			SetRemovedMessage(_searches.OutOfRangeAddress.Count());
 			UpdateList();
 			ToggleSearchDependentToolBarItems();
 		}
diff --git a/BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs b/BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs
index 8b49c7bc37..01acfe9cef 100644
--- a/BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs
+++ b/BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs
@@ -915,10 +915,8 @@ namespace BizHawk.Client.EmuHawk
 
 			Changes();
 
-			var indices = indexes.Select(t => t - 1).ToList();
-
 			WatchListView.SelectedIndices.Clear();
-			foreach (var t in indices)
+			foreach (var t in indexes.Select(t => t - 1))
 			{
 				WatchListView.SelectItem(t, true);
 			}
@@ -941,10 +939,8 @@ namespace BizHawk.Client.EmuHawk
 				_watches.Insert(indices[i] + 1, watch);
 			}
 
-			var newindices = indices.Select(t => t + 1).ToList();
-
 			WatchListView.SelectedIndices.Clear();
-			foreach (var t in newindices)
+			foreach (var t in indices.Select(t => t + 1))
 			{
 				WatchListView.SelectItem(t, true);
 			}
@@ -1298,11 +1294,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void ErrorIconButton_Click(object sender, EventArgs e)
 		{
-			var items = _watches
-				.Where(watch => watch.Address >= watch.Domain.Size)
-				.ToList();
-
-			foreach (var item in items)
+			foreach (var item in _watches.Where(watch => watch.Address >= watch.Domain.Size))
 			{
 				_watches.Remove(item);
 			}
diff --git a/BizHawk.Client.MultiHawk/Mainform.cs b/BizHawk.Client.MultiHawk/Mainform.cs
index 86654f0b44..34093dd56e 100644
--- a/BizHawk.Client.MultiHawk/Mainform.cs
+++ b/BizHawk.Client.MultiHawk/Mainform.cs
@@ -93,7 +93,7 @@ namespace BizHawk.Client.MultiHawk
 			{
 				Global.MovieSession.Movie.Stop();
 
-				foreach (var ew in EmulatorWindows.ToList())
+				foreach (var ew in EmulatorWindows)
 				{
 					ew.ShutDown();
 				}
@@ -1421,7 +1421,7 @@ namespace BizHawk.Client.MultiHawk
 
 		private void CloseAllWindows()
 		{
-			foreach (var ew in EmulatorWindows.ToList())
+			foreach (var ew in EmulatorWindows)
 			{
 				ew.Close();
 			}
@@ -1431,7 +1431,7 @@ namespace BizHawk.Client.MultiHawk
 
 		private void NewSessionMenuItem_Click(object sender, EventArgs e)
 		{
-			foreach (var ew in EmulatorWindows.ToList())
+			foreach (var ew in EmulatorWindows)
 			{
 				ew.Close();
 			}
diff --git a/BizHawk.Client.MultiHawk/movie/PlayMovie.cs b/BizHawk.Client.MultiHawk/movie/PlayMovie.cs
index 2b28df9ced..5c3aba3c17 100644
--- a/BizHawk.Client.MultiHawk/movie/PlayMovie.cs
+++ b/BizHawk.Client.MultiHawk/movie/PlayMovie.cs
@@ -300,13 +300,9 @@ namespace BizHawk.Client.MultiHawk
 
 		private void MovieView_DragDrop(object sender, DragEventArgs e)
 		{
-			var filePaths = (string[])e.Data.GetData(DataFormats.FileDrop);
-
-			filePaths
-				.Where(path => MovieService.MovieExtensions.Contains(Path.GetExtension(path).Replace(".", "")))
-				.ToList()
-				.ForEach(path => AddMovieToList(path, force: true));
-
+			foreach (var path in ((string[])e.Data.GetData(DataFormats.FileDrop))
+				.Where(path => MovieService.MovieExtensions.Contains(Path.GetExtension(path)?.Replace(".", ""))))
+					AddMovieToList(path, force: true);
 			RefreshMovieList();
 		}
 
@@ -459,11 +455,8 @@ namespace BizHawk.Client.MultiHawk
 
 		private void EditMenuItem_Click(object sender, EventArgs e)
 		{
-			MovieView.SelectedIndices
-				.Cast<int>()
-				.SelectAsIndexOf(_movieList)
-				.ToList()
-				.ForEach(movie => System.Diagnostics.Process.Start(movie.Filename));
+			foreach (var movie in MovieView.SelectedIndices.Cast<int>().SelectAsIndexOf(_movieList))
+				System.Diagnostics.Process.Start(movie.Filename);
 		}
 
 		#endregion
diff --git a/BizHawk.Common/BizInvoke/BizExvoker.cs b/BizHawk.Common/BizInvoke/BizExvoker.cs
index 120025f9cd..fd0678c5c8 100644
--- a/BizHawk.Common/BizInvoke/BizExvoker.cs
+++ b/BizHawk.Common/BizInvoke/BizExvoker.cs
@@ -58,19 +58,15 @@ namespace BizHawk.Common.BizInvoke
 
 			public DelegateStorage(Type type)
 			{
-				var methods = type.GetMethods(BindingFlags.Instance | BindingFlags.Public)
-				.Select(m => new
-				{
-					Info = m,
-					Attr = m.GetCustomAttributes(true).OfType<BizExportAttribute>().FirstOrDefault()
-				})
-				.Where(a => a.Attr != null)
-				.ToList();
-
 				var typeBuilder = ImplModuleBuilder.DefineType(
 					"Bizhawk.BizExvokeHolder" + type.Name, TypeAttributes.Class | TypeAttributes.Public | TypeAttributes.Sealed);
-
-				foreach (var a in methods)
+				foreach (var a in type.GetMethods(BindingFlags.Instance | BindingFlags.Public)
+					.Select(m => new
+						{
+							Info = m,
+							Attr = m.GetCustomAttributes(true).OfType<BizExportAttribute>().FirstOrDefault()
+						})
+					.Where(a => a.Attr != null))
 				{
 					MethodBuilder unused;
 					var delegateType = BizInvokeUtilities.CreateDelegateType(a.Info, a.Attr.CallingConvention, typeBuilder, out unused).CreateType();
diff --git a/BizHawk.Emulation.Common/ServiceAttributes.cs b/BizHawk.Emulation.Common/ServiceAttributes.cs
index 9d5fc2db9a..b06322065e 100644
--- a/BizHawk.Emulation.Common/ServiceAttributes.cs
+++ b/BizHawk.Emulation.Common/ServiceAttributes.cs
@@ -25,7 +25,7 @@ namespace BizHawk.Emulation.Common
 	{
 		public ServiceNotApplicableAttribute(params Type[] types)
 		{
-			NotApplicableTypes = types?.ToList() ?? new List<Type>();
+			NotApplicableTypes = types ?? Enumerable.Empty<Type>();
 		}
 
 		public IEnumerable<Type> NotApplicableTypes { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Computers/AmstradCPC/Hardware/Display/AmstradGateArray.cs b/BizHawk.Emulation.Cores/Computers/AmstradCPC/Hardware/Display/AmstradGateArray.cs
index 6c5033a324..8cd15d1cde 100644
--- a/BizHawk.Emulation.Cores/Computers/AmstradCPC/Hardware/Display/AmstradGateArray.cs
+++ b/BizHawk.Emulation.Cores/Computers/AmstradCPC/Hardware/Display/AmstradGateArray.cs
@@ -1034,13 +1034,9 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
         public int[] GetVideoBuffer()
         {
-            // get only lines that have pixel data
-            var lines = ScreenLines.Where(a => a.Pixels.Count > 0).ToList();
-            var height = lines.Count();
-
             int pos = 0;
             int lCount = 0;
-            foreach (var l in lines)
+            foreach (var l in ScreenLines.Where(a => a.Pixels.Count > 0)) // get only lines that have pixel data
             {
                 var lCop = l.Pixels.ToList();
                 var len = l.Pixels.Count;
diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.cs b/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.cs
index 436fdd3371..1882fc3d6f 100644
--- a/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.cs
@@ -75,7 +75,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 			{
 				Name = _game.Name,
 				System = "A26",
-				MetaData = "m=" + _mapper.GetType().ToString().Split('.').ToList().Last(),
+				MetaData = $"m={_mapper.GetType().ToString().Split('.').Last()}",
 				Hash = Rom.HashSHA1(),
 				Region = _game.Region,
 				Status = RomStatus.Unknown