diff --git a/src/lua_baselib.c b/src/lua_baselib.c
index d74af4214..f320cfdce 100644
--- a/src/lua_baselib.c
+++ b/src/lua_baselib.c
@@ -910,6 +910,28 @@ static int lib_pMaceRotate(lua_State *L)
 	return 0;
 }
 
+static int lib_pCreateFloorSpriteSlope(lua_State *L)
+{
+	mobj_t *mobj = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	NOHUD
+	INLEVEL
+	if (!mobj)
+		return LUA_ErrInvalid(L, "mobj_t");
+	LUA_PushUserdata(L, (pslope_t *)P_CreateFloorSpriteSlope(mobj), META_SLOPE);
+	return 1;
+}
+
+static int lib_pDeleteFloorSpriteSlope(lua_State *L)
+{
+	mobj_t *mobj = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	NOHUD
+	INLEVEL
+	if (!mobj)
+		return LUA_ErrInvalid(L, "mobj_t");
+	P_DeleteFloorSpriteSlope(mobj);
+	return 1;
+}
+
 static int lib_pRailThinker(lua_State *L)
 {
 	mobj_t *mobj = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
@@ -3536,6 +3558,8 @@ static luaL_Reg lib[] = {
 	{"P_CheckSolidLava",lib_pCheckSolidLava},
 	{"P_CanRunOnWater",lib_pCanRunOnWater},
 	{"P_MaceRotate",lib_pMaceRotate},
+	{"P_CreateFloorSpriteSlope",lib_pCreateFloorSpriteSlope},
+	{"P_DeleteFloorSpriteSlope",lib_pDeleteFloorSpriteSlope},
 	{"P_RailThinker",lib_pRailThinker},
 	{"P_XYMovement",lib_pXYMovement},
 	{"P_RingXYMovement",lib_pRingXYMovement},
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 6d36ee303..389dddecd 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -10473,8 +10473,7 @@ mobj_t *P_SpawnMobj(fixed_t x, fixed_t y, fixed_t z, mobjtype_t type)
 	// Sprite rendering
 	mobj->spritexscale = mobj->spriteyscale = mobj->scale;
 	mobj->spritexoffset = mobj->spriteyoffset = 0;
-	mobj->floorspriteslope = Z_Calloc(sizeof(pslope_t), PU_LEVEL, NULL);
-	mobj->floorspriteslope->normal.z = FRACUNIT;
+	mobj->floorspriteslope = NULL;
 
 	// set subsector and/or block links
 	P_SetThingPosition(mobj);
@@ -10876,6 +10875,22 @@ static inline precipmobj_t *P_SpawnSnowMobj(fixed_t x, fixed_t y, fixed_t z, mob
 	return mo;
 }
 
+void *P_CreateFloorSpriteSlope(mobj_t *mobj)
+{
+	if (mobj->floorspriteslope)
+		Z_Free(mobj->floorspriteslope);
+	mobj->floorspriteslope = Z_Calloc(sizeof(pslope_t), PU_LEVEL, NULL);
+	mobj->floorspriteslope->normal.z = FRACUNIT;
+	return (void *)mobj->floorspriteslope;
+}
+
+void P_DeleteFloorSpriteSlope(mobj_t *mobj)
+{
+	if (mobj->floorspriteslope)
+		Z_Free(mobj->floorspriteslope);
+	mobj->floorspriteslope = NULL;
+}
+
 //
 // P_RemoveMobj
 //
diff --git a/src/p_mobj.h b/src/p_mobj.h
index d26a38897..7eb47112c 100644
--- a/src/p_mobj.h
+++ b/src/p_mobj.h
@@ -472,6 +472,8 @@ void P_SpawnItemPattern(mapthing_t *mthing, boolean bonustime);
 void P_SpawnHoopOfSomething(fixed_t x, fixed_t y, fixed_t z, fixed_t radius, INT32 number, mobjtype_t type, angle_t rotangle);
 void P_SpawnPrecipitation(void);
 void P_SpawnParaloop(fixed_t x, fixed_t y, fixed_t z, fixed_t radius, INT32 number, mobjtype_t type, statenum_t nstate, angle_t rotangle, boolean spawncenter);
+void *P_CreateFloorSpriteSlope(mobj_t *mobj);
+void P_DeleteFloorSpriteSlope(mobj_t *mobj);
 boolean P_BossTargetPlayer(mobj_t *actor, boolean closest);
 boolean P_SupermanLook4Players(mobj_t *actor);
 void P_DestroyRobots(void);
diff --git a/src/p_saveg.c b/src/p_saveg.c
index ae8181693..6bd24214d 100644
--- a/src/p_saveg.c
+++ b/src/p_saveg.c
@@ -1620,7 +1620,7 @@ static void SaveMobjThinker(const thinker_t *th, const UINT8 type)
 		diff2 |= MD2_SPRITEYSCALE;
 	if (mobj->spritexoffset)
 		diff2 |= MD2_SPRITEXOFFSET;
-
+	if (mobj->floorspriteslope)
 	{
 		pslope_t *slope = mobj->floorspriteslope;
 		if (slope->zangle || slope->zdelta || slope->xydirection
@@ -2823,7 +2823,7 @@ static thinker_t* LoadMobjThinker(actionf_p1 thinker)
 		mobj->spriteyoffset = READFIXED(save_p);
 	if (diff2 & MD2_FLOORSPRITESLOPE)
 	{
-		pslope_t *slope = mobj->floorspriteslope;
+		pslope_t *slope = (pslope_t *)P_CreateFloorSpriteSlope(mobj);
 
 		slope->zdelta = READFIXED(save_p);
 		slope->zangle = READANGLE(save_p);