diff --git a/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.cpp b/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.cpp
index 69fd143..2131acf 100644
--- a/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.cpp
+++ b/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.cpp
@@ -7,24 +7,60 @@
 
 namespace jasper::world {
 
-EditWorldSize::EditWorldSize(WorldDoc &doc, ox::Size const&size):
+EditWorldSizeCommand::EditWorldSizeCommand(
+		ObjectCache const&objCache,
+		WorldDoc &doc,
+		WorldStatic &worldStatic,
+		ox::Size const&size):
+		m_objCache(objCache),
 		m_doc(doc),
+		m_worldStatic(worldStatic),
 		m_oldSize(m_doc.columns, m_doc.rows),
-		m_newVal(size) {
-}
+		m_newSize(size) {}
 
-void EditWorldSize::redo() noexcept {
+void EditWorldSizeCommand::redo() noexcept {
 	m_oldMap = m_doc.tiles;
-	resize(m_doc, m_newVal);
+	resize(m_doc, m_newSize);
+	oxLogError(loadWorldStatic(m_objCache, m_doc).moveTo(m_worldStatic));
 }
 
-void EditWorldSize::undo() noexcept {
+void EditWorldSizeCommand::undo() noexcept {
 	resize(m_doc, m_oldSize);
 	m_doc.tiles = std::move(m_oldMap);
+	oxLogError(loadWorldStatic(m_objCache, m_doc).moveTo(m_worldStatic));
 }
 
-int EditWorldSize::commandId() const noexcept {
+bool EditWorldSizeCommand::mergeWith(studio::UndoCommand const&cmd) noexcept {
+	auto const es = dynamic_cast<EditWorldSizeCommand const*>(&cmd);
+	if (!es || dimensionChanged() != es->dimensionChanged()) {
+		return false;
+	}
+	m_newSize = es->m_newSize;
+	// undo
+	resize(m_doc, m_oldSize);
+	m_doc.tiles = std::move(m_oldMap);
+	// redo
+	m_oldMap = m_doc.tiles;
+	resize(m_doc, m_newSize);
+	oxLogError(loadWorldStatic(m_objCache, m_doc).moveTo(m_worldStatic));
+	return true;
+}
+
+int EditWorldSizeCommand::commandId() const noexcept {
 	return static_cast<int>(WorldEditorCommand::EditWorldSize);
 }
 
+EditWorldSizeCommand::Dimension EditWorldSizeCommand::dimensionChanged() const noexcept {
+	auto const xChanged = m_oldSize.width == m_newSize.width;
+	auto const yChanged = m_oldSize.height == m_newSize.height;
+	if (xChanged && !yChanged) {
+		return Dimension::X;
+	} else if (!xChanged && yChanged) {
+		return Dimension::Y;
+	} else if (xChanged && yChanged) {
+		return Dimension::Both;
+	}
+	return Dimension::Neither;
+}
+
 }
diff --git a/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.hpp b/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.hpp
index 56f473d..9998d9c 100644
--- a/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.hpp
+++ b/src/jasper/modules/world/src/studio/worldeditor/commands/editsize.hpp
@@ -12,23 +12,36 @@
 
 namespace jasper::world {
 
-class EditWorldSize: public studio::UndoCommand {
+class EditWorldSizeCommand: public studio::UndoCommand {
 	private:
+		ObjectCache const&m_objCache;
 		WorldDoc &m_doc;
+		WorldStatic &m_worldStatic;
 		size_t m_insertIdx{};
 		ox::Size const m_oldSize;
 		WorldDoc::TileMap m_oldMap;
-		ox::Size const m_newVal;
+		ox::Size m_newSize;
 	public:
-		EditWorldSize(WorldDoc &doc, ox::Size const&size);
+		EditWorldSizeCommand(
+				ObjectCache const&objCache,
+				WorldDoc &doc,
+				WorldStatic &worldStatic,
+				ox::Size const&size);
 		void redo() noexcept override;
 		void undo() noexcept override;
+		bool mergeWith(studio::UndoCommand const&cmd) noexcept override;
 		[[nodiscard]]
 		int commandId() const noexcept override;
 		[[nodiscard]]
 		inline size_t insertIdx() const noexcept {
 			return m_insertIdx;
 		}
+	private:
+		enum class Dimension {
+			X, Y, Both, Neither,
+		};
+		[[nodiscard]]
+		Dimension dimensionChanged() const noexcept;
 };
 
 }
diff --git a/src/jasper/modules/world/src/studio/worldeditor/worldeditor-imgui.cpp b/src/jasper/modules/world/src/studio/worldeditor/worldeditor-imgui.cpp
index c38457e..f998cf3 100644
--- a/src/jasper/modules/world/src/studio/worldeditor/worldeditor-imgui.cpp
+++ b/src/jasper/modules/world/src/studio/worldeditor/worldeditor-imgui.cpp
@@ -54,7 +54,7 @@ static ox::Vec2 dropPos(ox::Vec2 dropPos) noexcept {
     return dropPos;
 }
 
-    [[nodiscard]]
+[[nodiscard]]
 constexpr ox::Point fbPtToTileAddr(
 		ox::Vec2 const&fbPt,
 		ox::Vec2 const&mapSz) noexcept {
@@ -159,10 +159,10 @@ void WorldEditorImGui::drawPropEditor() noexcept {
 	int width{m_doc.columns};
 	int height{m_doc.rows};
 	if (ImGui::InputInt("Map Width", &width, 1)) {
-		pushCommand<EditWorldSize>(m_doc, ox::Size{width, m_doc.rows});
+		pushCommand<EditWorldSizeCommand>(m_objCache, m_doc, m_worldStatic, ox::Size{width, m_doc.rows});
 	}
 	if (ImGui::InputInt("Map Height", &height, 1)) {
-		pushCommand<EditWorldSize>(m_doc, ox::Size{m_doc.columns, height});
+		pushCommand<EditWorldSizeCommand>(m_objCache, m_doc, m_worldStatic, ox::Size{m_doc.columns, height});
 	}
 }
 
diff --git a/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.cpp b/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.cpp
index a552abf..cdd328d 100644
--- a/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.cpp
+++ b/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.cpp
@@ -31,8 +31,8 @@ int EditObjectName::commandId() const noexcept {
 	return static_cast<int>(WorldObjCommand::EditObjectName);
 }
 
-bool EditObjectName::mergeWith(UndoCommand const*cmd) noexcept {
-	auto const en = dynamic_cast<EditObjectName const*>(cmd);
+bool EditObjectName::mergeWith(UndoCommand const&cmd) noexcept {
+	auto const en = dynamic_cast<EditObjectName const*>(&cmd);
 	if (en && m_objIdx == en->m_objIdx) {
 		m_newVal = en->m_newVal;
 		return true;
diff --git a/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.hpp b/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.hpp
index bb62cd5..82ffe2d 100644
--- a/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.hpp
+++ b/src/jasper/modules/world/src/studio/worldobjectseteditor/commands/editobject.hpp
@@ -24,7 +24,7 @@ class EditObjectName: public studio::UndoCommand {
 		void undo() noexcept override;
 		[[nodiscard]]
 		int commandId() const noexcept override;
-		bool mergeWith(UndoCommand const*cmd) noexcept override;
+		bool mergeWith(UndoCommand const&cmd) noexcept override;
 };
 
 class EditObjectSubSheet: public studio::UndoCommand {
diff --git a/src/jasper/modules/world/src/world.cpp b/src/jasper/modules/world/src/world.cpp
index 07d7499..d4eb17f 100644
--- a/src/jasper/modules/world/src/world.cpp
+++ b/src/jasper/modules/world/src/world.cpp
@@ -33,6 +33,7 @@ void World::setupLayer(
 		ncore::Context &ctx,
 		uint_t lyr,
 		uint_t cbb) const noexcept {
+	ncore::clearBg(ctx, lyr);
 	ncore::setBgStatus(ctx, lyr, true);
 	ncore::setBgCbb(ctx, lyr, cbb);
 	auto const rows = ox::min<int>(m_worldStatic.rows, ncore::tileRows(ctx) / 2);