diff --git a/src/app/core/common.h b/src/app/core/common.h
index ee20c559..c4ca3848 100644
--- a/src/app/core/common.h
+++ b/src/app/core/common.h
@@ -87,6 +87,9 @@ class ExperimentFlags {
 
       // Save overworld properties to the Rom.
       bool kSaveOverworldProperties = true;
+
+      // Load custom overworld data from the ROM and enable UI.
+      bool kLoadCustomOverworld = false;
     } overworld;
   };
 
diff --git a/src/app/editor/utils/flags.h b/src/app/editor/utils/flags.h
index 1616e83c..39b0eb4b 100644
--- a/src/app/editor/utils/flags.h
+++ b/src/app/editor/utils/flags.h
@@ -1,9 +1,8 @@
 #ifndef YAZE_APP_EDITOR_UTILS_FLAGS_H
 #define YAZE_APP_EDITOR_UTILS_FLAGS_H
 
-#include "imgui/imgui.h"
-
 #include "core/common.h"
+#include "imgui/imgui.h"
 
 namespace yaze {
 namespace app {
@@ -31,6 +30,8 @@ struct FlagsMenu : public core::ExperimentFlags {
                &mutable_flags()->overworld.kSaveOverworldItems);
       Checkbox("Save Overworld Properties",
                &mutable_flags()->overworld.kSaveOverworldProperties);
+      Checkbox("Load Custom Overworld",
+               &mutable_flags()->overworld.kLoadCustomOverworld);
       ImGui::EndMenu();
     }