diff --git a/src/gui/game/tool/ElementTool.cpp b/src/gui/game/tool/ElementTool.cpp
index 583d1af42..319cc6759 100644
--- a/src/gui/game/tool/ElementTool.cpp
+++ b/src/gui/game/tool/ElementTool.cpp
@@ -4,33 +4,33 @@
 #include "gui/game/Brush.h"
 
 void ElementTool::Draw(Simulation * sim, Brush const &brush, ui::Point position){
-	sim->CreateParts(position.X, position.Y, ToolID, brush);
+	sim->CreateParts(-2, position.X, position.Y, ToolID, brush, -1);
 }
 void ElementTool::DrawLine(Simulation * sim, Brush const &brush, ui::Point position1, ui::Point position2, bool dragging) {
-	sim->CreateLine(position1.X, position1.Y, position2.X, position2.Y, ToolID, brush);
+	sim->CreateLine(position1.X, position1.Y, position2.X, position2.Y, ToolID, brush, -1);
 }
 void ElementTool::DrawRect(Simulation * sim, Brush const &brush, ui::Point position1, ui::Point position2) {
-	sim->CreateBox(position1.X, position1.Y, position2.X, position2.Y, ToolID);
+	sim->CreateBox(-2, position1.X, position1.Y, position2.X, position2.Y, ToolID, -1);
 }
 void ElementTool::DrawFill(Simulation * sim, Brush const &brush, ui::Point position) {
-	sim->FloodParts(position.X, position.Y, ToolID, -1);
+	sim->FloodParts(position.X, position.Y, ToolID, -1, -1);
 }
 
 
 void Element_LIGH_Tool::DrawLine(Simulation * sim, Brush const &brush, ui::Point position1, ui::Point position2, bool dragging)
 {
 	if (dragging)
-		sim->CreateParts(position1.X, position1.Y, brush.GetRadius().X, brush.GetRadius().Y, PT_LIGH);
+		sim->CreateParts(-2, position1.X, position1.Y, brush.GetRadius().X, brush.GetRadius().Y, PT_LIGH, -1);
 }
 
 
 void Element_TESC_Tool::DrawRect(Simulation * sim, Brush const &brush, ui::Point position1, ui::Point position2) {
 	int radiusInfo = brush.GetRadius().X*4+brush.GetRadius().Y*4+7;
-	sim->CreateBox(position1.X, position1.Y, position2.X, position2.Y, ToolID | PMAPID(radiusInfo));
+	sim->CreateBox(-2, position1.X, position1.Y, position2.X, position2.Y, ToolID | PMAPID(radiusInfo), -1);
 }
 void Element_TESC_Tool::DrawFill(Simulation * sim, Brush const &brush, ui::Point position) {
 	int radiusInfo = brush.GetRadius().X*4+brush.GetRadius().Y*4+7;
-	sim->FloodParts(position.X, position.Y, ToolID | PMAPID(radiusInfo), -1);
+	sim->FloodParts(position.X, position.Y, ToolID | PMAPID(radiusInfo), -1, -1);
 }
 
 
diff --git a/src/lua/LuaSimulation.cpp b/src/lua/LuaSimulation.cpp
index fb535893b..34dbba9cb 100644
--- a/src/lua/LuaSimulation.cpp
+++ b/src/lua/LuaSimulation.cpp
@@ -332,6 +332,10 @@ static int partCreate(lua_State *L)
 		lua_pushinteger(L, -1);
 		return 1;
 	}
+	if (newID == -2)
+	{
+		lsi->AssertInterfaceEvent();
+	}
 	int type = lua_tointeger(L, 4);
 	int v = -1;
 	if (lua_gettop(L) >= 5)
@@ -509,7 +513,7 @@ static int createParts(lua_State *L)
 		RasterizeEllipseRows(Vec2<float>(rx * rx, ry * ry), [lsi, c, center](int xLim, int dy) {
 			for (auto pos : RectBetween(center + Vec2(-xLim, dy), center + Vec2(xLim, dy)))
 			{
-				lsi->sim->CreateParts(pos.X, pos.Y, 0, 0, c, 0);
+				lsi->sim->CreateParts(-1, pos.X, pos.Y, 0, 0, c, 0);
 			}
 		});
 		lua_pushinteger(L, 0); // return value doesn't make sense anyway
@@ -525,7 +529,7 @@ static int createParts(lua_State *L)
 	newBrush->SetRadius(ui::Point(rx, ry));
 
 	int c = luaL_optint(L,5,lsi->gameModel->GetActiveTool(0)->ToolID);
-	int ret = lsi->sim->CreateParts(x, y, c, *newBrush, uiFlags);
+	int ret = lsi->sim->CreateParts(-2, x, y, c, *newBrush, uiFlags);
 	lua_pushinteger(L, ret);
 	return 1;
 }
@@ -574,7 +578,7 @@ static int createBox(lua_State *L)
 	if (!(lsi->eventTraits & eventTraitInterface) && !lua_isnoneornil(L, 5) && flags == 0)
 	{
 		int c = luaL_checkint(L, 5); // note: weird: has to be specified in a sim context but not in a ui context
-		lsi->sim->CreateBox(x1, y1, x2, y2, c, 0);
+		lsi->sim->CreateBox(-1, x1, y1, x2, y2, c, 0);
 		return 0;
 	}
 
@@ -582,7 +586,7 @@ static int createBox(lua_State *L)
 	int c = luaL_optint(L,5,lsi->gameModel->GetActiveTool(0)->ToolID);
 	int uiFlags = luaL_optint(L,6,lsi->sim->replaceModeFlags);
 
-	lsi->sim->CreateBox(x1, y1, x2, y2, c, uiFlags);
+	lsi->sim->CreateBox(-2, x1, y1, x2, y2, c, uiFlags);
 	return 0;
 }
 
diff --git a/src/simulation/Editing.cpp b/src/simulation/Editing.cpp
index 29b689774..8b3ef2bbb 100644
--- a/src/simulation/Editing.cpp
+++ b/src/simulation/Editing.cpp
@@ -354,7 +354,7 @@ int Simulation::FloodWalls(int x, int y, int wall, int bm)
 	return 1;
 }
 
-int Simulation::CreatePartFlags(int x, int y, int c, int flags)
+int Simulation::CreatePartFlags(int p, int x, int y, int c, int flags)
 {
 	if (x < 0 || y < 0 || x >= XRES || y >= YRES)
 	{
@@ -397,7 +397,7 @@ int Simulation::CreatePartFlags(int x, int y, int c, int flags)
 	}
 	else
 	{
-		return (create_part(-2, x, y, TYP(c), ID(c)) == -1);
+		return (create_part(p, x, y, TYP(c), ID(c)) == -1);
 	}
 
 	// I'm sure at least one compiler exists that would complain if this wasn't here
@@ -738,7 +738,7 @@ void Simulation::ApplyDecorationFill(const RendererFrame &frame, int x, int y, i
 	free(bitmap);
 }
 
-int Simulation::CreateParts(int positionX, int positionY, int c, Brush const &cBrush, int flags)
+int Simulation::CreateParts(int p, int positionX, int positionY, int c, Brush const &cBrush, int flags)
 {
 	if (flags == -1)
 		flags = replaceModeFlags;
@@ -754,7 +754,7 @@ int Simulation::CreateParts(int positionX, int positionY, int c, Brush const &cB
 			newlife = 55;
 		c = PMAP(newlife, c);
 		lightningRecreate = currentTick + std::max(newlife / 4, 1);
-		return CreatePartFlags(positionX, positionY, c, flags);
+		return CreatePartFlags(p, positionX, positionY, c, flags);
 	}
 	else if (c == PT_TESC)
 	{
@@ -768,12 +768,12 @@ int Simulation::CreateParts(int positionX, int positionY, int c, Brush const &cB
 	{
 		ui::Point coords = ui::Point(positionX, positionY) + off;
 		if (coords.X >= 0 && coords.Y >= 0 && coords.X < XRES && coords.Y < YRES)
-			CreatePartFlags(coords.X, coords.Y, c, flags);
+			CreatePartFlags(p, coords.X, coords.Y, c, flags);
 	}
 	return 0;
 }
 
-int Simulation::CreateParts(int x, int y, int rx, int ry, int c, int flags)
+int Simulation::CreateParts(int p, int x, int y, int rx, int ry, int c, int flags)
 {
 	bool created = false;
 
@@ -802,7 +802,7 @@ int Simulation::CreateParts(int x, int y, int rx, int ry, int c, int flags)
 
 	for (int j = -ry; j <= ry; j++)
 		for (int i = -rx; i <= rx; i++)
-			if (CreatePartFlags(x+i, y+j, c, flags))
+			if (CreatePartFlags(p, x+i, y+j, c, flags))
 				created = true;
 	return !created;
 }
@@ -838,9 +838,9 @@ void Simulation::CreateLine(int x1, int y1, int x2, int y2, int c, Brush const &
 	for (x=x1; x<=x2; x++)
 	{
 		if (reverseXY)
-			CreateParts(y, x, c, cBrush, flags);
+			CreateParts(-2, y, x, c, cBrush, flags);
 		else
-			CreateParts(x, y, c, cBrush, flags);
+			CreateParts(-2, x, y, c, cBrush, flags);
 		e += de;
 		if (e >= 0.5f)
 		{
@@ -848,16 +848,16 @@ void Simulation::CreateLine(int x1, int y1, int x2, int y2, int c, Brush const &
 			if (!(rx+ry) && ((y1<y2) ? (y<=y2) : (y>=y2)))
 			{
 				if (reverseXY)
-					CreateParts(y, x, c, cBrush, flags);
+					CreateParts(-2, y, x, c, cBrush, flags);
 				else
-					CreateParts(x, y, c, cBrush, flags);
+					CreateParts(-2, x, y, c, cBrush, flags);
 			}
 			e -= 1.0f;
 		}
 	}
 }
 
-void Simulation::CreateBox(int x1, int y1, int x2, int y2, int c, int flags)
+void Simulation::CreateBox(int p, int x1, int y1, int x2, int y2, int c, int flags)
 {
 	int i, j;
 	if (x1>x2)
@@ -874,7 +874,7 @@ void Simulation::CreateBox(int x1, int y1, int x2, int y2, int c, int flags)
 	}
 	for (j=y2; j>=y1; j--)
 		for (i=x1; i<=x2; i++)
-			CreateParts(i, j, 0, 0, c, flags);
+			CreateParts(p, i, j, 0, 0, c, flags);
 }
 
 int Simulation::FloodParts(int x, int y, int fullc, int cm, int flags)
@@ -974,7 +974,7 @@ int Simulation::FloodParts(int x, int y, int fullc, int cm, int flags)
 					created_something = 1;
 				}
 			}
-			else if (CreateParts(x, y, 0, 0, fullc, flags))
+			else if (CreateParts(-2, x, y, 0, 0, fullc, flags))
 				created_something = 1;
 			bitmap[(y * XRES) + x] = 1;
 		}
diff --git a/src/simulation/Simulation.h b/src/simulation/Simulation.h
index 12c7ca2f2..7601c22df 100644
--- a/src/simulation/Simulation.h
+++ b/src/simulation/Simulation.h
@@ -220,19 +220,19 @@ public:
 	void ApplyDecorationFill(const RendererFrame &frame, int x, int y, int colR, int colG, int colB, int colA, int replaceR, int replaceG, int replaceB);
 
 	//Drawing Walls
-	int CreateWalls(int x, int y, int rx, int ry, int wall, Brush const *cBrush = nullptr);
-	void CreateWallLine(int x1, int y1, int x2, int y2, int rx, int ry, int wall, Brush const *cBrush = nullptr);
+	int CreateWalls(int x, int y, int rx, int ry, int wall, Brush const *cBrush);
+	void CreateWallLine(int x1, int y1, int x2, int y2, int rx, int ry, int wall, Brush const *cBrush);
 	void CreateWallBox(int x1, int y1, int x2, int y2, int wall);
 	int FloodWalls(int x, int y, int wall, int bm);
 
 	//Drawing Particles
-	int CreateParts(int positionX, int positionY, int c, Brush const &cBrush, int flags = -1);
-	int CreateParts(int x, int y, int rx, int ry, int c, int flags = -1);
-	int CreatePartFlags(int x, int y, int c, int flags);
-	void CreateLine(int x1, int y1, int x2, int y2, int c, Brush const &cBrush, int flags = -1);
+	int CreateParts(int p, int positionX, int positionY, int c, Brush const &cBrush, int flags);
+	int CreateParts(int p, int x, int y, int rx, int ry, int c, int flags);
+	int CreatePartFlags(int p, int x, int y, int c, int flags);
+	void CreateLine(int x1, int y1, int x2, int y2, int c, Brush const &cBrush, int flags);
 	void CreateLine(int x1, int y1, int x2, int y2, int c);
-	void CreateBox(int x1, int y1, int x2, int y2, int c, int flags = -1);
-	int FloodParts(int x, int y, int c, int cm, int flags = -1);
+	void CreateBox(int p, int x1, int y1, int x2, int y2, int c, int flags);
+	int FloodParts(int x, int y, int c, int cm, int flags);
 
 	void GetGravityField(int x, int y, float particleGrav, float newtonGrav, float & pGravX, float & pGravY);