diff --git a/build/premake/premake5.lua b/build/premake/premake5.lua
index 4ea7049b1e..dfc1a52f9e 100644
--- a/build/premake/premake5.lua
+++ b/build/premake/premake5.lua
@@ -1306,14 +1306,15 @@ function setup_atlas_projects()
 	setup_atlas_project("AtlasObject", "StaticLib",
 	{	-- src
 		".",
-		"../../../third_party/jsonspirit"
-
 	},{	-- include
-		"../../../third_party/jsonspirit"
+		"../../../",
 	},{	-- extern_libs
 		"boost",
 		"iconv",
-		"libxml2"
+		"libxml2",
+		"sdl",
+		"spidermonkey",
+		"cxxtest",
 	},{	-- extra_params
 		no_pch = 1
 	})
@@ -1367,10 +1368,6 @@ function setup_atlas_projects()
 	setup_atlas_project("AtlasUI", "SharedLib", atlas_src,
 	{	-- include
 		"../../..",
-		"..",
-		"CustomControls",
-		"Misc",
-		"../../../third_party/jsonspirit"
 	},
 	atlas_extern_libs,
 	{	-- extra_params
diff --git a/source/lib/external_libraries/libsdl.h b/source/lib/external_libraries/libsdl.h
index 8aee8c494d..f2a791fad1 100644
--- a/source/lib/external_libraries/libsdl.h
+++ b/source/lib/external_libraries/libsdl.h
@@ -30,8 +30,8 @@
 #include "lib/config2.h"
 #include "lib/external_libraries/libsdl_fwd.h"
 
-# include "SDL.h"
-# include "SDL_thread.h"
+# include <SDL.h>
+# include <SDL_thread.h>
 
 #if !SDL_VERSION_ATLEAST(2,0,2)
 #error You are using an old libsdl release. At least libsdl2 >= 2.0.2 is required.
@@ -41,7 +41,7 @@
 // in static bswap routines. doesn't matter - modern compilers
 // will strip them if unused, and this is more convenient than
 // another header that toggles between wsdl and SDL_endian.h.
-# include "SDL_endian.h"
+# include <SDL_endian.h>
 
 // complete definition of our forward-declared SDL_Event (see sdl_fwd.h)
 struct SDL_Event_
diff --git a/source/lib/sysdep/os/win/win.h b/source/lib/sysdep/os/win/win.h
index 7ccc8c7ca0..004b3ac5eb 100644
--- a/source/lib/sysdep/os/win/win.h
+++ b/source/lib/sysdep/os/win/win.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
@@ -27,6 +27,8 @@
 #ifndef INCLUDED_WIN
 #define INCLUDED_WIN
 
+#include "lib/sysdep/os.h"
+
 #if !OS_WIN
 #error "win.h: do not include if not compiling for Windows"
 #endif
diff --git a/source/test_setup.cpp b/source/test_setup.cpp
index dcf6a7b9e2..2729b1aa91 100644
--- a/source/test_setup.cpp
+++ b/source/test_setup.cpp
@@ -26,17 +26,29 @@
 
 #include "lib/self_test.h"
 
+#include "lib/code_generation.h"
+#include "lib/debug.h"
+#include "lib/os_path.h"
+#include "lib/path.h"
+#include "lib/sysdep/compiler.h"
+#include "lib/sysdep/os.h"
 #include "lib/sysdep/sysdep.h"
 #include "lib/timer.h"
+#include "lib/utf8.h"
 #include "ps/Profiler2.h"
 #include "ps/TaskManager.h"
+#include "ps/ThreadUtil.h"
 #include "scriptinterface/FunctionWrapper.h"
 #include "scriptinterface/ScriptContext.h"
 #include "scriptinterface/ScriptEngine.h"
 #include "scriptinterface/ScriptInterface.h"
+#include "scriptinterface/ScriptRequest.h"
 
 #include <fstream>
+#include <iterator>
+#include <memory>
 #include <optional>
+#include <string>
 
 class LeakReporter : public CxxTest::GlobalFixture
 {
diff --git a/source/tools/atlas/AtlasObject/AtlasObject.h b/source/tools/atlas/AtlasObject/AtlasObject.h
index 68657809d9..3239e3be35 100644
--- a/source/tools/atlas/AtlasObject/AtlasObject.h
+++ b/source/tools/atlas/AtlasObject/AtlasObject.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -30,8 +30,6 @@
 
 #include <string>
 
-class wxString;
-
 //////////////////////////////////////////////////////////////////////////
 // Mostly-private bits:
 
diff --git a/source/tools/atlas/AtlasObject/JSONSpiritInclude.h b/source/tools/atlas/AtlasObject/JSONSpiritInclude.h
index 8e34ff7aeb..beea6094de 100644
--- a/source/tools/atlas/AtlasObject/JSONSpiritInclude.h
+++ b/source/tools/atlas/AtlasObject/JSONSpiritInclude.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -29,8 +29,8 @@
  #pragma warning(disable: 4512)
 #endif
 
-# include "json_spirit_writer_template.h"
-# include "json_spirit_reader_template.h"
+# include "third_party/jsonspirit/json_spirit_writer_template.h"
+# include "third_party/jsonspirit/json_spirit_reader_template.h"
 
 #ifdef _MSC_VER
  #pragma warning(default: 4100)
diff --git a/source/tools/atlas/AtlasObject/tests/test_AtlasObjectXML.h b/source/tools/atlas/AtlasObject/tests/test_AtlasObjectXML.h
index f60c70b1e5..30ce5add1c 100644
--- a/source/tools/atlas/AtlasObject/tests/test_AtlasObjectXML.h
+++ b/source/tools/atlas/AtlasObject/tests/test_AtlasObjectXML.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,7 +17,9 @@
 
 #include "lib/self_test.h"
 
-#include "../AtlasObject.h"
+#include "tools/atlas/AtlasObject/AtlasObject.h"
+
+#include <string>
 
 class TestAtlasObjectXML : public CxxTest::TestSuite
 {
diff --git a/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.cpp b/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.cpp
index 0862a5dfd9..55459a17eb 100644
--- a/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.cpp
+++ b/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.cpp
@@ -21,6 +21,7 @@
 
 #include "tools/atlas/AtlasObject/AtlasObject.h"
 #include "tools/atlas/AtlasUI/ActorEditor/ActorEditorListCtrl.h"
+#include "tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.h"
 #include "tools/atlas/AtlasUI/General/Datafile.h"
 
 #include <boost/algorithm/string/predicate.hpp>
diff --git a/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.h b/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.h
index 1a9754878b..269a257e46 100644
--- a/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.h
+++ b/source/tools/atlas/AtlasUI/ActorEditor/ActorEditor.h
@@ -15,9 +15,8 @@
  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "Windows/AtlasWindow.h"
-
 #include "tools/atlas/AtlasObject/AtlasObject.h"
+#include "tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.h"
 
 #include <wx/defs.h>
 #include <wx/event.h>
diff --git a/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.cpp b/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.cpp
index fde507cad3..68574c625e 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.cpp
@@ -25,7 +25,6 @@
 
 #include <algorithm>
 #include <wx/debug.h>
-#include <wx/rtti.h>
 #include <wx/translation.h>
 
 //////////////////////////////////////////////////////////////////////////
diff --git a/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.h b/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.h
index 8576ca4624..73b5c80433 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.h
+++ b/source/tools/atlas/AtlasUI/CustomControls/DraggableListCtrl/DraggableListCtrlCommands.h
@@ -23,7 +23,6 @@
 #include <wx/object.h>
 
 class DraggableListCtrl;
-class wxClassInfo;
 
 class DragCommand : public AtlasWindowCommand
 {
diff --git a/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/EditableListCtrlCommands.cpp b/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/EditableListCtrlCommands.cpp
index 7071bff357..1501a656ba 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/EditableListCtrlCommands.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/EditableListCtrlCommands.cpp
@@ -23,7 +23,6 @@
 #include "tools/atlas/AtlasUI/CustomControls/EditableListCtrl/EditableListCtrl.h"
 #include "tools/atlas/AtlasUI/General/AtlasWindowCommand.h"
 
-#include <wx/rtti.h>
 #include <wx/translation.h>
 
 //////////////////////////////////////////////////////////////////////////
diff --git a/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/QuickFileCtrl.cpp b/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/QuickFileCtrl.cpp
index a955c511ed..5895bf2db0 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/QuickFileCtrl.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/EditableListCtrl/QuickFileCtrl.cpp
@@ -30,7 +30,6 @@
 #include <wx/filename.h>
 #include <wx/gdicmn.h>
 #include <wx/log.h>
-#include <wx/rtti.h>
 #include <wx/sizer.h>
 #include <wx/string.h>
 #include <wx/textctrl.h>
diff --git a/source/tools/atlas/AtlasUI/CustomControls/HighResTimer/HighResTimer.cpp b/source/tools/atlas/AtlasUI/CustomControls/HighResTimer/HighResTimer.cpp
index 42ee5cd5da..996d7aa62a 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/HighResTimer/HighResTimer.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/HighResTimer/HighResTimer.cpp
@@ -25,6 +25,11 @@
 
 #ifdef __WXMSW__
 
+#include "lib/sysdep/os/win/win.h"
+
+#include <wx/intl.h>
+#include <wx/log.h>
+
 HighResTimer::HighResTimer()
 {
 	LARGE_INTEGER freq;
diff --git a/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.cpp b/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.cpp
index 5aebe5255f..ea4184cce4 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.cpp
@@ -23,11 +23,12 @@
 
 #include "virtualdirtreectrl.h"
 
-#include "wx/imaglist.h"
 #include <wx/bitmap.h>
 #include <wx/busyinfo.h>
 #include <wx/dir.h>
 #include <wx/filefn.h>
+#include <wx/filename.h>
+#include <wx/imaglist.h>
 #include <wx/log.h>
 #include <wx/translation.h>
 
diff --git a/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.h b/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.h
index 1515688a76..0c8785e959 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.h
+++ b/source/tools/atlas/AtlasUI/CustomControls/VirtualDirTreeCtrl/virtualdirtreectrl.h
@@ -23,21 +23,21 @@
 #define INCLUDED_VIRTUALDIRTREECTRL
 
 #include <cstdlib>
-#include <cstring>
 #include <wx/arrstr.h>
 #include <wx/chartype.h>
 #include <wx/debug.h>
 #include <wx/defs.h>
 #include <wx/dynarray.h>
 #include <wx/event.h>
-#include <wx/filename.h>
-#include <wx/gdicmn.h>
 #include <wx/string.h>
 #include <wx/toolbar.h>
 #include <wx/treebase.h>
 #include <wx/treectrl.h>
 #include <wx/validate.h>
 
+class wxFileName;
+class wxPoint;
+class wxSize;
 class wxBitmap;
 class wxImageList;
 class wxWindow;
diff --git a/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasDialog.cpp b/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasDialog.cpp
index 3898cf3542..80f6c7cf4c 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasDialog.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasDialog.cpp
@@ -24,7 +24,6 @@
 #include <wx/accel.h>
 #include <wx/button.h>
 #include <wx/panel.h>
-#include <wx/rtti.h>
 #include <wx/sizer.h>
 #include <wx/statline.h>
 #include <wx/toolbar.h>
diff --git a/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.cpp b/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.cpp
index 6da18067f6..c9ce2756a4 100644
--- a/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.cpp
+++ b/source/tools/atlas/AtlasUI/CustomControls/Windows/AtlasWindow.cpp
@@ -43,7 +43,6 @@
 #include <wx/log.h>
 #include <wx/menu.h>
 #include <wx/menuitem.h>
-#include <wx/rtti.h>
 #include <wx/sizer.h>
 #include <wx/statbmp.h>
 #include <wx/stattext.h>
diff --git a/source/tools/atlas/AtlasUI/General/AtlasWindowCommand.cpp b/source/tools/atlas/AtlasUI/General/AtlasWindowCommand.cpp
index 89892aef0f..18c6266e17 100644
--- a/source/tools/atlas/AtlasUI/General/AtlasWindowCommand.cpp
+++ b/source/tools/atlas/AtlasUI/General/AtlasWindowCommand.cpp
@@ -24,7 +24,6 @@
 
 #include <wx/cmdproc.h>
 #include <wx/log.h>
-#include <wx/rtti.h>
 #include <wx/translation.h>
 
 IMPLEMENT_ABSTRACT_CLASS(AtlasWindowCommand, wxCommand);
diff --git a/source/tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h b/source/tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h
index a3f1329699..907c412cf1 100644
--- a/source/tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h
+++ b/source/tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h
@@ -18,7 +18,7 @@
 #ifndef INCLUDED_ATLASWINDOWCOMMANDPROC
 #define INCLUDED_ATLASWINDOWCOMMANDPROC
 
-#include "wx/cmdproc.h"
+#include <wx/cmdproc.h>
 
 class wxWindow;
 
diff --git a/source/tools/atlas/AtlasUI/General/IAtlasSerialiser.h b/source/tools/atlas/AtlasUI/General/IAtlasSerialiser.h
index a47dc8c4d6..673feb7672 100644
--- a/source/tools/atlas/AtlasUI/General/IAtlasSerialiser.h
+++ b/source/tools/atlas/AtlasUI/General/IAtlasSerialiser.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,7 +18,7 @@
 #ifndef INCLUDED_IATLASSERIALISER
 #define INCLUDED_IATLASSERIALISER
 
-#include "AtlasObject/AtlasObject.h"
+#include "tools/atlas/AtlasObject/AtlasObject.h"
 
 // An interface for GUI components to transfer their contents to/from AtObjs.
 // (Maybe "serialise" isn't quite correct, since AtObjs aren't serial, but
diff --git a/source/tools/atlas/AtlasUI/Misc/precompiled.h b/source/tools/atlas/AtlasUI/Misc/precompiled.h
index 8371cc46c6..027f518f39 100644
--- a/source/tools/atlas/AtlasUI/Misc/precompiled.h
+++ b/source/tools/atlas/AtlasUI/Misc/precompiled.h
@@ -45,33 +45,33 @@
 #endif
 
 // Include useful wx headers
-#include "wx/wxprec.h"
+#include <wx/wxprec.h>
 
-#include "wx/artprov.h"
-#include "wx/cmdproc.h"
-#include "wx/colordlg.h"
-#include "wx/config.h"
-#include "wx/dialog.h"
-#include "wx/dir.h"
-#include "wx/dnd.h"
-#include "wx/docview.h"
-#include "wx/file.h"
-#include "wx/filename.h"
-#include "wx/filesys.h"
-#include "wx/glcanvas.h"
-#include "wx/image.h"
-#include "wx/listctrl.h"
-#include "wx/mstream.h"
-#include "wx/notebook.h"
-#include "wx/progdlg.h"
-#include "wx/regex.h"
-#include "wx/sound.h"
-#include "wx/spinctrl.h"
-#include "wx/splitter.h"
-#include "wx/tooltip.h"
-#include "wx/treectrl.h"
-#include "wx/wfstream.h"
-#include "wx/zstream.h"
+#include <wx/artprov.h>
+#include <wx/cmdproc.h>
+#include <wx/colordlg.h>
+#include <wx/config.h>
+#include <wx/dialog.h>
+#include <wx/dir.h>
+#include <wx/dnd.h>
+#include <wx/docview.h>
+#include <wx/file.h>
+#include <wx/filename.h>
+#include <wx/filesys.h>
+#include <wx/glcanvas.h>
+#include <wx/image.h>
+#include <wx/listctrl.h>
+#include <wx/mstream.h>
+#include <wx/notebook.h>
+#include <wx/progdlg.h>
+#include <wx/regex.h>
+#include <wx/sound.h>
+#include <wx/spinctrl.h>
+#include <wx/splitter.h>
+#include <wx/tooltip.h>
+#include <wx/treectrl.h>
+#include <wx/wfstream.h>
+#include <wx/zstream.h>
 
 #ifdef __GNUC__
 # pragma GCC diagnostic pop
@@ -101,13 +101,10 @@
 # endif
 #endif
 
-#else // HAVE_PCH
-
-// If no PCH, just include the most common headers anyway
-# include "wx/wx.h"
-
 #endif // HAVE_PCH
 
+#include <wx/platform.h>
+#include <wx/version.h>
 // wxWidgets 3.0 or later required
 #if !wxCHECK_VERSION(3, 0, 0)
 # error You are using an old wxWidgets release. At least wxWidgets >= 3.0.0 is required.
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.cpp
index fe6c966de2..b7a807c06b 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.cpp
@@ -19,37 +19,61 @@
 
 #include "ScenarioEditor.h"
 
+#include "tools/atlas/AtlasObject/AtlasObject.h"
+#include "tools/atlas/AtlasUI/CustomControls/Buttons/ToolButton.h"
+#include "tools/atlas/AtlasUI/CustomControls/Canvas/Canvas.h"
+#include "tools/atlas/AtlasUI/CustomControls/FileHistory/FileHistory.h"
+#include "tools/atlas/AtlasUI/CustomControls/HighResTimer/HighResTimer.h"
+#include "tools/atlas/AtlasUI/CustomControls/MapDialog/MapDialog.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/General/Datafile.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
 #include "tools/atlas/AtlasUI/Misc/DLLInterface.h"
+#include "tools/atlas/AtlasUI/Misc/KeyMap.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
 
-#include "wx/busyinfo.h"
-#include "wx/clipbrd.h"
-#include "wx/config.h"
-#include "wx/dir.h"
-#include "wx/evtloop.h"
-#include "wx/ffile.h"
-#include "wx/filename.h"
-#include "wx/image.h"
-#include "wx/sstream.h"
-#include "wx/sysopt.h"
-#include "wx/tooltip.h"
-#include "wx/xml/xml.h"
+#include <cstddef>
+#include <list>
+#include <string>
+#include <utility>
+#include <wx/busyinfo.h>
+#include <wx/chartype.h>
+#include <wx/clipbrd.h>
+#include <wx/config.h>
+#include <wx/dataobj.h>
+#include <wx/datetime.h>
+#include <wx/debug.h>
+#include <wx/ffile.h>
+#include <wx/filedlg.h>
+#include <wx/filefn.h>
+#include <wx/filename.h>
+#include <wx/gdicmn.h>
+#include <wx/glcanvas.h>
+#include <wx/imagbmp.h>
+#include <wx/image.h>
+#include <wx/imagpng.h>
+#include <wx/log.h>
+#include <wx/menu.h>
+#include <wx/msgdlg.h>
+#include <wx/sstream.h>
+#include <wx/sysopt.h>
+#include <wx/textdlg.h>
+#include <wx/toolbar.h>
+#include <wx/tooltip.h>
+#include <wx/toplevel.h>
+#include <wx/translation.h>
+#include <wx/utils.h>
+#include <wx/xml/xml.h>
 
-#include "General/AtlasEventLoop.h"
-#include "General/Datafile.h"
-
-#include "CustomControls/Buttons/ToolButton.h"
-#include "CustomControls/Canvas/Canvas.h"
-#include "CustomControls/HighResTimer/HighResTimer.h"
-#include "CustomControls/MapDialog/MapDialog.h"
-
-#include "GameInterface/MessagePasser.h"
-#include "GameInterface/Messages.h"
-
-#include "Misc/KeyMap.h"
-
-#include "Tools/Common/Tools.h"
-#include "Tools/Common/Brushes.h"
-#include "Tools/Common/MiscState.h"
+class wxInputStream;
+class wxWindow;
 
 static HighResTimer g_Timer;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h b/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h
index d97943cb7b..e3132da702 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,16 +18,25 @@
 #ifndef INCLUDED_SCENARIOEDITOR
 #define INCLUDED_SCENARIOEDITOR
 
-#include "wx/toolbar.h"
-
-#include "General/AtlasWindowCommandProc.h"
-#include "General/Observable.h"
-#include "Tools/Common/ObjectSettings.h"
-#include "Tools/Common/Tools.h"
-#include "CustomControls/FileHistory/FileHistory.h"
-#include "SectionLayout.h"
+#include "tools/atlas/AtlasObject/AtlasObject.h"
+#include "tools/atlas/AtlasUI/CustomControls/FileHistory/FileHistory.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
 
 #include <map>
+#include <vector>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/frame.h>
+#include <wx/icon.h>
+#include <wx/string.h>
+#include <wx/timer.h>
+
+class AtlasWindowCommandProc;
+class wxWindow;
 
 class ScenarioEditor : public wxFrame
 {
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.cpp
index 26e7002d42..f39a025892 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,18 +19,39 @@
 
 #include "SectionLayout.h"
 
-#include "CustomControls/SnapSplitterWindow/SnapSplitterWindow.h"
-#include "General/Datafile.h"
-#include "ScenarioEditor.h"
-#include "Sections/Cinema/Cinema.h"
-#include "Sections/Environment/Environment.h"
-#include "Sections/Map/Map.h"
-#include "Sections/Object/Object.h"
-#include "Sections/Player/Player.h"
-#include "Sections/Terrain/Terrain.h"
+#include "tools/atlas/AtlasUI/CustomControls/SnapSplitterWindow/SnapSplitterWindow.h"
+#include "tools/atlas/AtlasUI/General/Datafile.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Cinema/Cinema.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Common/Sidebar.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Environment/Environment.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Map/Map.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Object/Object.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Player/Player.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Terrain/Terrain.h"
 
+#include <cstddef>
+#include <utility>
+#include <vector>
+#include <wx/bitmap.h>
+#include <wx/bmpbndl.h>
+#include <wx/bmpbuttn.h>
+#include <wx/chartype.h>
+#include <wx/colour.h>
+#include <wx/defs.h>
+#include <wx/event.h>
 #include <wx/filename.h>
+#include <wx/gdicmn.h>
+#include <wx/image.h>
+#include <wx/log.h>
+#include <wx/panel.h>
+#include <wx/settings.h>
+#include <wx/sizer.h>
+#include <wx/splitter.h>
+#include <wx/string.h>
+#include <wx/toolbar.h>
+#include <wx/translation.h>
 #include <wx/wfstream.h>
+#include <wx/window.h>
 
 //////////////////////////////////////////////////////////////////////////
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h b/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h
index 85d3b79872..7df6e80d68 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/SectionLayout.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -21,6 +21,12 @@
 #include <map>
 #include <string>
 
+class ScenarioEditor;
+class SidebarBook;
+class SnapSplitterWindow;
+class wxString;
+class wxWindow;
+
 // Some platform dependent sizes
 #if defined(__WXGTK__)
 	#define SIDEBAR_SIZE 285
@@ -33,11 +39,6 @@
 	#define BOTTOMBAR_SIZE 180
 #endif
 
-class ScenarioEditor;
-class SnapSplitterWindow;
-class SidebarBook;
-class wxWindow;
-
 class SectionLayout
 {
 public:
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Object/Object.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Object/Object.cpp
index e27dbd480f..6872767c16 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Object/Object.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Object/Object.cpp
@@ -51,7 +51,6 @@
 #include <wx/listbox.h>
 #include <wx/object.h>
 #include <wx/panel.h>
-#include <wx/rtti.h>
 #include <wx/scrolwin.h>
 #include <wx/sizer.h>
 #include <wx/stattext.h>
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Terrain/Terrain.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Terrain/Terrain.cpp
index 9af9f520f6..1608a6f1f3 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Terrain/Terrain.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Sections/Terrain/Terrain.cpp
@@ -41,6 +41,7 @@
 #include <vector>
 #include <wx/arrstr.h>
 #include <wx/bitmap.h>
+#include <wx/bmpbuttn.h>
 #include <wx/bookctrl.h>
 #include <wx/busyinfo.h>
 #include <wx/button.h>
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ActorViewerTool.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ActorViewerTool.cpp
index d4d7fd9b30..f81aeb770c 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ActorViewerTool.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ActorViewerTool.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,12 +17,23 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "Common/ObjectSettings.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <algorithm>
+#include <cmath>
+#include <list>
+#include <vector>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/mousestate.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/AlterElevation.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/AlterElevation.cpp
index bed2f0452d..a20b1d8358 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/AlterElevation.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/AlterElevation.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,10 +17,18 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.cpp
index 6140cb8326..1a6f140573 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,9 +19,24 @@
 
 #include "Brushes.h"
 
-#include "GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
 
-#include "wx/spinctrl.h"
+#include <cmath>
+#include <cstddef>
+#include <wx/arrstr.h>
+#include <wx/chartype.h>
+#include <wx/debug.h>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/radiobox.h>
+#include <wx/sizer.h>
+#include <wx/spinbutt.h>
+#include <wx/spinctrl.h>
+#include <wx/stattext.h>
+#include <wx/string.h>
+#include <wx/toolbar.h>
+#include <wx/translation.h>
 
 Brush g_Brush_Elevation; // shared between several elevation-related tools; other tools have their own brushes
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h
index 0f03ae9104..e3492ecec9 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,12 +18,11 @@
 #ifndef INCLUDED_BRUSHES
 #define INCLUDED_BRUSHES
 
-class BrushShapeCtrl;
-class BrushSizeCtrl;
-class BrushStrengthCtrl;
-
 #include <vector>
 
+class wxSizer;
+class wxWindow;
+
 class Brush
 {
 	friend class BrushShapeCtrl;
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.cpp
index 89fbfd0db0..cd78af260d 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,6 +19,10 @@
 
 #include "MiscState.h"
 
+#include "tools/atlas/AtlasUI/General/Observable.h"
+
+#include <wx/string.h>
+
 Observable<wxString> g_SelectedTexture;
 
 Observable<std::vector<AtlasMessage::ObjectID> > g_SelectedObjects;
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h
index 60b9f89ac9..4f90c961a7 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,7 +18,10 @@
 #ifndef INCLUDED_MISCSTATE
 #define INCLUDED_MISCSTATE
 
-#include "General/Observable.h"
+#include <vector>
+
+class wxString;
+template <typename T> class Observable;
 
 namespace AtlasMessage
 {
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.cpp
index 95e3421b85..55f5595217 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,8 +19,16 @@
 
 #include "ObjectSettings.h"
 
-#include "GameInterface/Messages.h"
-#include "ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <cstddef>
+#include <list>
+#include <string>
 
 ObjectSettings::ObjectSettings(Observable<std::vector<AtlasMessage::ObjectID> >& selectedObjects, int view)
 : m_PlayerID(0), m_SelectedObjects(selectedObjects), m_View(view)
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h
index e89c56455d..e8936c172a 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,10 +18,13 @@
 #ifndef INCLUDED_OBJECTSETTINGS
 #define INCLUDED_OBJECTSETTINGS
 
-#include <vector>
-#include <set>
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
 
-#include "ScenarioEditor/Tools/Common/MiscState.h"
+#include <set>
+#include <vector>
+#include <wx/arrstr.h>
+#include <wx/string.h>
 
 namespace AtlasMessage
 {
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.cpp
index 5f1eb44b61..fc4f37a7eb 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,8 +18,18 @@
 #include "precompiled.h"
 
 #include "Tools.h"
-#include "GameInterface/Messages.h"
-#include "CustomControls/Buttons/ToolButton.h"
+
+#include "tools/atlas/AtlasUI/CustomControls/Buttons/ToolButton.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommand.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+
+#include <list>
+#include <vector>
+#include <wx/object.h>
+#include <wx/string.h>
+#include <wx/toolbar.h>
 
 class DummyTool : public ITool
 {
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h
index 38888b0983..25d92df774 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2014 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,12 +18,20 @@
 #ifndef INCLUDED_TOOLS
 #define INCLUDED_TOOLS
 
-#include "General/AtlasWindowCommand.h"
-#include "General/Observable.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommand.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h" // IWYU pragma: keep - required for POST_COMMAND
+
+#include <cstddef>
+#include <wx/debug.h>
+#include <wx/defs.h>
+#include <wx/object.h>
 
-class wxMouseEvent;
-class wxKeyEvent;
 class ScenarioEditor;
+class wxKeyEvent;
+class wxMouseEvent;
+class wxString;
+class wxToolBar;
+template <typename T> class ObservablePtr;
 
 class ITool : public wxObject
 {
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FillTerrain.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FillTerrain.cpp
index 2f6e521eb7..8ff15a9c14 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FillTerrain.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FillTerrain.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,20 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <string>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/object.h>
+#include <wx/string.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FlattenElevation.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FlattenElevation.cpp
index 3e8b750bf7..439e95c65e 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FlattenElevation.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/FlattenElevation.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,10 +17,18 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PaintTerrain.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PaintTerrain.cpp
index aca48f35ee..02ce5cad2e 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PaintTerrain.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PaintTerrain.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,24 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <list>
+#include <string>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
+#include <wx/string.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PickWaterHeight.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PickWaterHeight.cpp
index f7940f1d43..9e3912cbfb 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PickWaterHeight.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PickWaterHeight.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,16 @@
 
 #include "precompiled.h"
 
-#include "Common/Tools.h"
-#include "Common/MiscState.h"
-#include "GameInterface/Messages.h"
-#include "ScenarioEditor/Sections/Environment/Environment.h"
-#include "ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Sections/Environment/Environment.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <wx/debug.h>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PikeElevation.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PikeElevation.cpp
index cb17ce60e8..486b102679 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PikeElevation.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PikeElevation.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2013 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,10 +17,18 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PlaceObject.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PlaceObject.cpp
index 3aedf8b433..e00f3c6641 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PlaceObject.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/PlaceObject.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,15 +17,25 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "Common/ObjectSettings.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
 
+#include <cmath>
 #include <ctime>
+#include <list>
 #include <random>
+#include <string>
+#include <wx/chartype.h>
+#include <wx/debug.h>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/object.h>
+#include <wx/string.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ReplaceTerrain.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ReplaceTerrain.cpp
index dd54169680..b10b572788 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ReplaceTerrain.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/ReplaceTerrain.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,20 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <string>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/object.h>
+#include <wx/string.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/SmoothElevation.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/SmoothElevation.cpp
index 574bfe8ff6..b2ed8fadbe 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/SmoothElevation.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/SmoothElevation.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,18 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Brushes.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
 
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
index ca233ec619..b9b6ddefde 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformObject.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,15 +17,37 @@
 
 #include "precompiled.h"
 
-#include "ScenarioEditor/ScenarioEditor.h"
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "Common/ObjectSettings.h"
-#include "GameInterface/Messages.h"
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/General/Observable.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/MiscState.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/ObjectSettings.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
+
+#include <algorithm>
+#include <cstddef>
+#include <limits>
+#include <list>
+#include <string>
+#include <vector>
+#include <wx/chartype.h>
 #include <wx/clipbrd.h>
-#include <wx/xml/xml.h>
+#include <wx/dataobj.h>
+#include <wx/debug.h>
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 #include <wx/sstream.h>
+#include <wx/string.h>
+#include <wx/utils.h>
+#include <wx/xml/xml.h>
+
+class wxInputStream;
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformPath.cpp b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformPath.cpp
index 3ab9195f82..fdf757b6c0 100644
--- a/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformPath.cpp
+++ b/source/tools/atlas/AtlasUI/ScenarioEditor/Tools/TransformPath.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,18 +17,18 @@
 
 #include "precompiled.h"
 
-#include "Common/Tools.h"
-#include "Common/Brushes.h"
-#include "Common/MiscState.h"
-#include "Common/ObjectSettings.h"
-#include "GameInterface/Messages.h"
-#include "ScenarioEditor/ScenarioEditor.h"
-
-#include <wx/clipbrd.h>
-#include <wx/sstream.h>
-#include <wx/version.h>
-#include <wx/xml/xml.h>
+#include "tools/atlas/AtlasUI/General/AtlasWindowCommandProc.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/ScenarioEditor.h"
+#include "tools/atlas/AtlasUI/ScenarioEditor/Tools/Common/Tools.h"
+#include "tools/atlas/GameInterface/MessagePasser.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
+#include "tools/atlas/GameInterface/SharedTypes.h"
 
+#include <wx/defs.h>
+#include <wx/event.h>
+#include <wx/gdicmn.h>
+#include <wx/object.h>
 
 using AtlasMessage::Position;
 
diff --git a/source/tools/atlas/GameInterface/ActorViewer.cpp b/source/tools/atlas/GameInterface/ActorViewer.cpp
index 28adb59bdf..0e11ef6d27 100644
--- a/source/tools/atlas/GameInterface/ActorViewer.cpp
+++ b/source/tools/atlas/GameInterface/ActorViewer.cpp
@@ -47,6 +47,7 @@
 #include "maths/Matrix3D.h"
 #include "maths/Vector3D.h"
 #include "ps/CLogger.h"
+#include "ps/CStr.h"
 #include "ps/Filesystem.h"
 #include "ps/ProfileViewer.h"
 #include "ps/VideoMode.h"
diff --git a/source/tools/atlas/GameInterface/Handlers/CommandHandlers.cpp b/source/tools/atlas/GameInterface/Handlers/CommandHandlers.cpp
index d50aecca42..d2ba213c87 100644
--- a/source/tools/atlas/GameInterface/Handlers/CommandHandlers.cpp
+++ b/source/tools/atlas/GameInterface/Handlers/CommandHandlers.cpp
@@ -17,9 +17,16 @@
 
 #include "precompiled.h"
 
-#include "MessageHandler.h"
+#include "lib/debug.h"
+#include "tools/atlas/GameInterface/CommandProc.h"
+#include "tools/atlas/GameInterface/Handlers/MessageHandler.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/Shareable.h"
 
-#include "../CommandProc.h"
+#include <cstddef>
+#include <map>
+#include <string>
+#include <utility>
 
 namespace AtlasMessage {
 
diff --git a/source/tools/atlas/GameInterface/Handlers/MessageHandler.h b/source/tools/atlas/GameInterface/Handlers/MessageHandler.h
index 385cf10873..044682a4f0 100644
--- a/source/tools/atlas/GameInterface/Handlers/MessageHandler.h
+++ b/source/tools/atlas/GameInterface/Handlers/MessageHandler.h
@@ -18,7 +18,8 @@
 #ifndef INCLUDED_MESSAGEHANDLER
 #define INCLUDED_MESSAGEHANDLER
 
-#include "../Messages.h"
+#include "lib/debug.h"
+#include "tools/atlas/GameInterface/Messages.h"
 
 #include <map>
 #include <string>
diff --git a/source/tools/atlas/GameInterface/MessagePasserImpl.cpp b/source/tools/atlas/GameInterface/MessagePasserImpl.cpp
index 3daeb2b263..fe2be0d505 100644
--- a/source/tools/atlas/GameInterface/MessagePasserImpl.cpp
+++ b/source/tools/atlas/GameInterface/MessagePasserImpl.cpp
@@ -17,14 +17,18 @@
 
 #include "precompiled.h"
 
-#include <cstdio>
-
 #include "MessagePasserImpl.h"
-#include "Messages.h"
-#include "Handlers/MessageHandler.h"
 
+#include "lib/debug.h"
 #include "lib/timer.h"
 #include "ps/CLogger.h"
+#include "tools/atlas/GameInterface/Handlers/MessageHandler.h"
+#include "tools/atlas/GameInterface/Messages.h"
+#include "tools/atlas/GameInterface/SharedMemory.h"
+
+#include <map>
+#include <string>
+#include <utility>
 
 using namespace AtlasMessage;
 
diff --git a/source/tools/atlas/GameInterface/Messages.h b/source/tools/atlas/GameInterface/Messages.h
index 40ba13d494..27acf7d03c 100644
--- a/source/tools/atlas/GameInterface/Messages.h
+++ b/source/tools/atlas/GameInterface/Messages.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -24,7 +24,7 @@
 
 // Opens namespace AtlasMessage, closes it on second inclusion!
 #ifndef MESSAGES_SKIP_SETUP
-#include "MessagesSetup.h"
+#include "MessagesSetup.h" // IWYU pragma: keep
 #endif
 
 // TODO: organisation, documentation, etc
@@ -746,7 +746,7 @@ QUERY(GetSelectedObjectsTemplateNames,
 
 
 #ifndef MESSAGES_SKIP_SETUP
-#include "MessagesSetup.h"
+#include "MessagesSetup.h" // IWYU pragma: keep
 #endif
 
 #endif // INCLUDED_MESSAGES
diff --git a/source/tools/atlas/GameInterface/Shareable.h b/source/tools/atlas/GameInterface/Shareable.h
index bd1059529c..e7b3119dc6 100644
--- a/source/tools/atlas/GameInterface/Shareable.h
+++ b/source/tools/atlas/GameInterface/Shareable.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -57,16 +57,19 @@ after their definition.
 
 */
 
-#include "SharedMemory.h"
-
-#include <cstring>
-#include <vector>
-#include <string>
-
 // we want to use placement new without grief
 // (Duplicated in SharedMemory.h)
 #undef new
 
+#include "tools/atlas/GameInterface/SharedMemory.h"
+
+#include <cstring>
+#include <new>
+#include <string>
+#include <vector>
+
+namespace AtlasMessage { template <typename T> class Shareable; }
+
 namespace AtlasMessage
 {
 
diff --git a/source/tools/atlas/GameInterface/SharedMemory.h b/source/tools/atlas/GameInterface/SharedMemory.h
index 928f83ed92..d20be126a1 100644
--- a/source/tools/atlas/GameInterface/SharedMemory.h
+++ b/source/tools/atlas/GameInterface/SharedMemory.h
@@ -18,12 +18,13 @@
 #ifndef INCLUDED_SHAREDMEMORY
 #define INCLUDED_SHAREDMEMORY
 
-#include <cstddef>
-
 // we want to use placement new without grief
 // (Duplicated in Shareable.h)
 #undef new
 
+#include <cstddef>
+#include <new>
+
 namespace AtlasMessage
 {
 
diff --git a/source/tools/atlas/GameInterface/SharedTypes.h b/source/tools/atlas/GameInterface/SharedTypes.h
index ae90580ee9..087c9faaa5 100644
--- a/source/tools/atlas/GameInterface/SharedTypes.h
+++ b/source/tools/atlas/GameInterface/SharedTypes.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -21,6 +21,7 @@
 #include "Shareable.h"
 
 #include <string>
+#include <vector>
 
 class wxPoint;
 class CVector3D;