diff --git a/src/GameState.cpp b/src/GameState.cpp
index cac1631f9a..c673779f02 100644
--- a/src/GameState.cpp
+++ b/src/GameState.cpp
@@ -2918,6 +2918,59 @@ public:
 		COMMON_RETURN_SELF;
 	}
 
+	static int SetStepsForEditMode(T* p, lua_State *L)
+	{
+		// Arg forms:
+		// 1.  Edit existing steps:
+		//    song, steps
+		// 2.  Create new steps to edit:
+		//    song, nil, stepstype, difficulty
+		// 3.  Copy steps to new difficulty to edit:
+		//    song, steps, stepstype, difficulty
+		Song* song= Luna<Song>::check(L, 1);
+		Steps* steps= NULL;
+		if(!lua_isnil(L, 2))
+		{
+			steps= Luna<Steps>::check(L, 2);
+		}
+		// Form 1.
+		if(steps != NULL && lua_gettop(L) == 2)
+		{
+			p->m_pCurSong.Set(song);
+			p->m_pCurSteps[PLAYER_1].Set(steps);
+			p->SetCurrentStyle(GAMEMAN->GetEditorStyleForStepsType(
+					steps->m_StepsType), PLAYER_INVALID);
+			p->m_pCurCourse.Set(NULL);
+			return 0;
+		}
+		StepsType stype= Enum::Check<StepsType>(L, 3);
+		Difficulty diff= Enum::Check<Difficulty>(L, 4);
+		Steps* new_steps= song->CreateSteps();
+		RString edit_name;
+		// Form 2.
+		if(steps == NULL)
+		{
+			new_steps->CreateBlank(stype);
+			new_steps->SetMeter(1);
+			edit_name= "";
+		}
+		// Form 3.
+		else
+		{
+			new_steps->CopyFrom(steps, stype, song->m_fMusicLengthSeconds);
+			edit_name= steps->GetDescription();
+		}
+		SongUtil::MakeUniqueEditDescription(song, stype, edit_name);
+		steps->SetDescription(edit_name);
+		song->AddSteps(new_steps);
+		p->m_pCurSong.Set(song);
+		p->m_pCurSteps[PLAYER_1].Set(steps);
+		p->SetCurrentStyle(GAMEMAN->GetEditorStyleForStepsType(
+				steps->m_StepsType), PLAYER_INVALID);
+		p->m_pCurCourse.Set(NULL);
+		return 0;
+	}
+
 	LunaGameState()
 	{
 		ADD_METHOD( IsPlayerEnabled );
@@ -3000,7 +3053,6 @@ public:
 		ADD_METHOD( IsWinner );
 		ADD_METHOD( IsDraw );
 		ADD_METHOD( GetCurrentGame );
-		//ADD_METHOD( SetCurrentGame );
 		ADD_METHOD( GetEditCourseEntryIndex );
 		ADD_METHOD( GetEditLocalProfileID );
 		ADD_METHOD( GetEditLocalProfile );
@@ -3042,6 +3094,7 @@ public:
 		ADD_METHOD( StoreRankingName );
 		ADD_METHOD( SetCurrentStyle );
 		ADD_METHOD( SetCurrentPlayMode );
+		ADD_METHOD( SetStepsForEditMode );
 	}
 };