diff --git a/src/doomdata.h b/src/doomdata.h
index ef08ecaba..f3342e0cd 100644
--- a/src/doomdata.h
+++ b/src/doomdata.h
@@ -153,30 +153,30 @@ enum
 
 	// Transfers FOF properties.
 	ML_TFERLINE			= 0x00008000,
-
-	// Special action is repeatable.
-	ML_REPEATSPECIAL	= 0x00010000,
 };
 
 enum
 {
+	// Special action is repeatable.
+	SPAC_REPEATSPECIAL		= 0x00000001,
+
 	// Activates when crossed by a player.
-	SPAC_CROSS				= 0x00000001,
+	SPAC_CROSS				= 0x00000002,
 
 	// Activates when crossed by an enemy.
-	SPAC_CROSSMONSTER		= 0x00000002,
+	SPAC_CROSSMONSTER		= 0x00000004,
 
 	// Activates when crossed by a projectile.
-	SPAC_CROSSMISSILE		= 0x00000004,
+	SPAC_CROSSMISSILE		= 0x00000008,
 
 	// Activates when bumped by a player.
-	SPAC_PUSH				= 0x00000008,
+	SPAC_PUSH				= 0x00000010,
 
 	// Activates when bumped by an enemy.
-	SPAC_PUSHMONSTER		= 0x00000010,
+	SPAC_PUSHMONSTER		= 0x00000020,
 
 	// Activates when bumped by a missile.
-	SPAC_IMPACT				= 0x00000020,
+	SPAC_IMPACT				= 0x00000040,
 };
 
 // Sector definition, from editing.
diff --git a/src/lua_baselib.c b/src/lua_baselib.c
index 971834a8b..09cab84f1 100644
--- a/src/lua_baselib.c
+++ b/src/lua_baselib.c
@@ -204,6 +204,9 @@ static const struct {
 	{META_LINEARGS,     "line_t.args"},
 	{META_LINESTRINGARGS, "line_t.stringargs"},
 
+	{META_SECTORARGS,     "sector_t.args"},
+	{META_SECTORSTRINGARGS, "sector_t.stringargs"},
+
 	{META_THINGARGS,     "mapthing.args"},
 	{META_THINGSTRINGARGS, "mapthing.stringargs"},
 #ifdef HAVE_LUA_SEGS
diff --git a/src/lua_libs.h b/src/lua_libs.h
index 265cf8bc8..2d32a9eb5 100644
--- a/src/lua_libs.h
+++ b/src/lua_libs.h
@@ -77,6 +77,8 @@ extern lua_State *gL;
 #define META_SIDENUM "LINE_T*SIDENUM"
 #define META_LINEARGS "LINE_T*ARGS"
 #define META_LINESTRINGARGS "LINE_T*STRINGARGS"
+#define META_SECTORARGS "SECTOR_T*ARGS"
+#define META_SECTORSTRINGARGS "SECTOR_T*STRINGARGS"
 #define META_THINGARGS "MAPTHING_T*ARGS"
 #define META_THINGSTRINGARGS "MAPTHING_T*STRINGARGS"
 #define META_POLYOBJVERTICES "POLYOBJ_T*VERTICES"
diff --git a/src/lua_maplib.c b/src/lua_maplib.c
index d7492c466..a9353be0f 100644
--- a/src/lua_maplib.c
+++ b/src/lua_maplib.c
@@ -56,6 +56,10 @@ enum sector_e {
 	sector_triggerer,
 	sector_friction,
 	sector_gravity,
+	sector_action,
+	sector_args,
+	sector_stringargs,
+	sector_activation,
 };
 
 static const char *const sector_opt[] = {
@@ -86,6 +90,10 @@ static const char *const sector_opt[] = {
 	"triggerer",
 	"friction",
 	"gravity",
+	"action",
+	"args"
+	"stringargs",
+	"activation",
 	NULL};
 
 enum subsector_e {
@@ -592,6 +600,42 @@ static int sectorlines_num(lua_State *L)
 // sector_t //
 //////////////
 
+// args, i -> args[i]
+static int sectorargs_get(lua_State *L)
+{
+	INT32 *args = *((INT32**)luaL_checkudata(L, 1, META_SECTORARGS));
+	int i = luaL_checkinteger(L, 2);
+	if (i < 0 || i >= NUMSECTORARGS)
+		return luaL_error(L, LUA_QL("sector_t.args") " index cannot be %d", i);
+	lua_pushinteger(L, args[i]);
+	return 1;
+}
+
+// #args -> NUMSECTORARGS
+static int sectorargs_len(lua_State* L)
+{
+	lua_pushinteger(L, NUMSECTORARGS);
+	return 1;
+}
+
+// stringargs, i -> stringargs[i]
+static int sectorstringargs_get(lua_State *L)
+{
+	char **stringargs = *((char***)luaL_checkudata(L, 1, META_SECTORSTRINGARGS));
+	int i = luaL_checkinteger(L, 2);
+	if (i < 0 || i >= NUMSECTORSTRINGARGS)
+		return luaL_error(L, LUA_QL("line_t.stringargs") " index cannot be %d", i);
+	lua_pushstring(L, stringargs[i]);
+	return 1;
+}
+
+// #stringargs -> NUMLINESTRINGARGS
+static int sectorstringargs_len(lua_State *L)
+{
+	lua_pushinteger(L, NUMSECTORSTRINGARGS);
+	return 1;
+}
+
 static int sector_get(lua_State *L)
 {
 	sector_t *sector = *((sector_t **)luaL_checkudata(L, 1, META_SECTOR));
@@ -710,6 +754,18 @@ static int sector_get(lua_State *L)
 	case sector_gravity: // gravity
 		lua_pushfixed(L, sector->gravity);
 		return 1;
+	case sector_action: // action
+		lua_pushinteger(L, (INT16)sector->action);
+		return 1;
+	case sector_args:
+		LUA_PushUserdata(L, sector->args, META_SECTORARGS);
+		return 1;
+	case sector_stringargs:
+		LUA_PushUserdata(L, sector->stringargs, META_SECTORSTRINGARGS);
+		return 1;
+	case sector_activation: // activation
+		lua_pushinteger(L, sector->activation);
+		return 1;
 	}
 	return 0;
 }
@@ -738,6 +794,8 @@ static int sector_set(lua_State *L)
 	case sector_fslope: // f_slope
 	case sector_cslope: // c_slope
 	case sector_friction: // friction
+	case sector_args: // args
+	case sector_stringargs: // stringargs
 	default:
 		return luaL_error(L, "sector_t field " LUA_QS " cannot be set.", sector_opt[field]);
 	case sector_floorheight: { // floorheight
@@ -816,6 +874,12 @@ static int sector_set(lua_State *L)
 	case sector_gravity:
 		sector->gravity = luaL_checkfixed(L, 3);
 		break;
+	case sector_action:
+		sector->action = (INT16)luaL_checkinteger(L, 3);
+		break;
+	case sector_activation:
+		sector->activation = luaL_checkinteger(L, 3);
+		break;
 	}
 	return 0;
 }
@@ -2570,6 +2634,22 @@ int LUA_MapLib(lua_State *L)
 		lua_setfield(L, -2, "__len");
 	lua_pop(L, 1);
 
+	luaL_newmetatable(L, META_SECTORARGS);
+		lua_pushcfunction(L, sectorargs_get);
+		lua_setfield(L, -2, "__index");
+
+		lua_pushcfunction(L, sectorargs_len);
+		lua_setfield(L, -2, "__len");
+	lua_pop(L, 1);
+
+	luaL_newmetatable(L, META_SECTORSTRINGARGS);
+		lua_pushcfunction(L, sectorstringargs_get);
+		lua_setfield(L, -2, "__index");
+
+		lua_pushcfunction(L, sectorstringargs_len);
+		lua_setfield(L, -2, "__len");
+	lua_pop(L, 1);
+
 	luaL_newmetatable(L, META_SUBSECTOR);
 		lua_pushcfunction(L, subsector_get);
 		lua_setfield(L, -2, "__index");
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 183f292c4..870aa77c6 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -9810,6 +9810,9 @@ void P_MobjThinker(mobj_t *mobj)
 	P_SetTarget(&tm.floorthing, NULL);
 	P_SetTarget(&tm.hitthing, NULL);
 
+	// Check for sector special actions
+	P_CheckMobjTouchingSectorActions(mobj);
+
 	// Sector flag MSF_TRIGGERLINE_MOBJ allows ANY mobj to trigger a linedef exec
 	P_CheckMobjTrigger(mobj, false);
 
diff --git a/src/p_saveg.c b/src/p_saveg.c
index 319916f98..47a85c3df 100644
--- a/src/p_saveg.c
+++ b/src/p_saveg.c
@@ -1099,8 +1099,40 @@ static void P_NetUnArchiveColormaps(savebuffer_t *save)
 //diff4 flags
 #define SD_DAMAGETYPE 0x01
 #define SD_TRIGGERTAG 0x02
-#define SD_TRIGGERER 0x04
-#define SD_GRAVITY   0x08
+#define SD_TRIGGERER  0x04
+#define SD_GRAVITY    0x08
+#define SD_ACTION     0x10
+#define SD_ARGS       0x20
+#define SD_STRINGARGS 0x40
+#define SD_DIFF5      0x80
+
+//diff5 flags
+#define SD_ACTIVATION 0x01
+
+static boolean P_SectorArgsEqual(const sector_t *sc, const sector_t *spawnsc)
+{
+	UINT8 i;
+	for (i = 0; i < NUMSECTORARGS; i++)
+		if (sc->args[i] != spawnsc->args[i])
+			return false;
+
+	return true;
+}
+
+static boolean P_SectorStringArgsEqual(const sector_t *sc, const sector_t *spawnsc)
+{
+	UINT8 i;
+	for (i = 0; i < NUMSECTORSTRINGARGS; i++)
+	{
+		if (!sc->stringargs[i])
+			return !spawnsc->stringargs[i];
+
+		if (strcmp(sc->stringargs[i], spawnsc->stringargs[i]))
+			return false;
+	}
+
+	return true;
+}
 
 #define LD_FLAG     0x01
 #define LD_SPECIAL  0x02
@@ -1124,7 +1156,7 @@ static void P_NetUnArchiveColormaps(savebuffer_t *save)
 // diff3 flags
 #define LD_ACTIVATION    0x01
 
-static boolean P_AreArgsEqual(const line_t *li, const line_t *spawnli)
+static boolean P_LineArgsEqual(const line_t *li, const line_t *spawnli)
 {
 	UINT8 i;
 	for (i = 0; i < NUMLINEARGS; i++)
@@ -1134,7 +1166,7 @@ static boolean P_AreArgsEqual(const line_t *li, const line_t *spawnli)
 	return true;
 }
 
-static boolean P_AreStringArgsEqual(const line_t *li, const line_t *spawnli)
+static boolean P_LineStringArgsEqual(const line_t *li, const line_t *spawnli)
 {
 	UINT8 i;
 	for (i = 0; i < NUMLINESTRINGARGS; i++)
@@ -1243,11 +1275,11 @@ static void ArchiveSectors(savebuffer_t *save)
 	size_t i, j;
 	const sector_t *ss = sectors;
 	const sector_t *spawnss = spawnsectors;
-	UINT8 diff, diff2, diff3, diff4;
+	UINT8 diff, diff2, diff3, diff4, diff5;
 
 	for (i = 0; i < numsectors; i++, ss++, spawnss++)
 	{
-		diff = diff2 = diff3 = diff4 = 0;
+		diff = diff2 = diff3 = diff4 = diff5 = 0;
 		if (ss->floorheight != spawnss->floorheight)
 			diff |= SD_FLOORHT;
 		if (ss->ceilingheight != spawnss->ceilingheight)
@@ -1303,9 +1335,21 @@ static void ArchiveSectors(savebuffer_t *save)
 		if (ss->gravity != spawnss->gravity)
 			diff4 |= SD_GRAVITY;
 
+		if (ss->action != spawnss->action)
+			diff4 |= SD_ACTION;
+		if (!P_SectorArgsEqual(ss, spawnss))
+			diff4 |= SD_ARGS;
+		if (!P_SectorStringArgsEqual(ss, spawnss))
+			diff4 |= SD_STRINGARGS;
+		if (ss->activation != spawnss->activation)
+			diff5 |= SD_ACTIVATION;
+
 		if (ss->ffloors && CheckFFloorDiff(ss))
 			diff |= SD_FFLOORS;
 
+		if (diff5)
+			diff4 |= SD_DIFF5;
+
 		if (diff4)
 			diff3 |= SD_DIFF4;
 
@@ -1383,6 +1427,35 @@ static void ArchiveSectors(savebuffer_t *save)
 				WRITEUINT8(save->p, ss->triggerer);
 			if (diff4 & SD_GRAVITY)
 				WRITEFIXED(save->p, ss->gravity);
+
+			if (diff4 & SD_ACTION)
+				WRITEINT16(save->p, ss->action);
+			if (diff4 & SD_ARGS)
+			{
+				for (j = 0; j < NUMSECTORARGS; j++)
+					WRITEINT32(save->p, ss->args[j]);
+			}
+			if (diff4 & SD_STRINGARGS)
+			{
+				for (j = 0; j < NUMSECTORSTRINGARGS; j++)
+				{
+					size_t len, k;
+
+					if (!ss->stringargs[j])
+					{
+						WRITEINT32(save->p, 0);
+						continue;
+					}
+
+					len = strlen(ss->stringargs[j]);
+					WRITEINT32(save->p, len);
+					for (k = 0; k < len; k++)
+						WRITECHAR(save->p, ss->stringargs[j][k]);
+				}
+			}
+			if (diff5 & SD_ACTIVATION)
+				WRITEUINT32(save->p, ss->activation);
+
 			if (diff & SD_FFLOORS)
 				ArchiveFFloors(save, ss);
 		}
@@ -1394,7 +1467,7 @@ static void ArchiveSectors(savebuffer_t *save)
 static void UnArchiveSectors(savebuffer_t *save)
 {
 	UINT16 i, j;
-	UINT8 diff, diff2, diff3, diff4;
+	UINT8 diff, diff2, diff3, diff4, diff5;
 	for (;;)
 	{
 		i = READUINT16(save->p);
@@ -1419,6 +1492,11 @@ static void UnArchiveSectors(savebuffer_t *save)
 		else
 			diff4 = 0;
 
+		if (diff4 & SD_DIFF5)
+			diff5 = READUINT8(save->p);
+		else
+			diff5 = 0;
+
 		if (diff & SD_FLOORHT)
 			sectors[i].floorheight = READFIXED(save->p);
 		if (diff & SD_CEILHT)
@@ -1504,6 +1582,36 @@ static void UnArchiveSectors(savebuffer_t *save)
 		if (diff4 & SD_GRAVITY)
 			sectors[i].gravity = READFIXED(save->p);
 
+		if (diff4 & SD_ACTION)
+			sectors[i].action = READINT16(save->p);
+		if (diff4 & SD_ARGS)
+		{
+			for (j = 0; j < NUMSECTORARGS; j++)
+				sectors[i].args[j] = READINT32(save->p);
+		}
+		if (diff4 & SD_STRINGARGS)
+		{
+			for (j = 0; j < NUMLINESTRINGARGS; j++)
+			{
+				size_t len = READINT32(save->p);
+				size_t k;
+
+				if (!len)
+				{
+					Z_Free(sectors[i].stringargs[j]);
+					sectors[i].stringargs[j] = NULL;
+					continue;
+				}
+
+				sectors[i].stringargs[j] = Z_Realloc(sectors[i].stringargs[j], len + 1, PU_LEVEL, NULL);
+				for (k = 0; k < len; k++)
+					sectors[i].stringargs[j][k] = READCHAR(save->p);
+				sectors[i].stringargs[j][len] = '\0';
+			}
+		}
+		if (diff5 & SD_ACTIVATION)
+			sectors[i].activation = READUINT32(save->p);
+
 		if (diff & SD_FFLOORS)
 			UnArchiveFFloors(save, &sectors[i]);
 	}
@@ -1531,10 +1639,10 @@ static void ArchiveLines(savebuffer_t *save)
 		if (spawnli->special == 321 || spawnli->special == 322) // only reason li->callcount would be non-zero is if either of these are involved
 			diff |= LD_CLLCOUNT;
 
-		if (!P_AreArgsEqual(li, spawnli))
+		if (!P_LineArgsEqual(li, spawnli))
 			diff2 |= LD_ARGS;
 
-		if (!P_AreStringArgsEqual(li, spawnli))
+		if (!P_LineStringArgsEqual(li, spawnli))
 			diff2 |= LD_STRINGARGS;
 
 		if (li->executordelay != spawnli->executordelay)
diff --git a/src/p_setup.c b/src/p_setup.c
index 1fe9e2f12..2bb1f40b5 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -870,6 +870,11 @@ static void P_LoadSectors(UINT8 *data)
 
 		ss->friction = ORIG_FRICTION;
 
+		ss->action = 0;
+		memset(ss->args, 0, NUMLINEARGS*sizeof(*ss->args));
+		memset(ss->stringargs, 0x00, NUMLINESTRINGARGS*sizeof(*ss->stringargs));
+		ss->activation = 0;
+
 		P_InitializeSector(ss);
 	}
 }
@@ -980,6 +985,7 @@ static void P_LoadLinedefs(UINT8 *data)
 		memset(ld->stringargs, 0x00, NUMLINESTRINGARGS*sizeof(*ld->stringargs));
 		ld->alpha = FRACUNIT;
 		ld->executordelay = 0;
+		ld->activation = 0;
 		P_SetLinedefV1(i, SHORT(mld->v1));
 		P_SetLinedefV2(i, SHORT(mld->v2));
 
@@ -1216,6 +1222,7 @@ static void P_LoadThings(UINT8 *data)
 		mt->scale = mapobjectscale;
 		memset(mt->args, 0, NUMMAPTHINGARGS*sizeof(*mt->args));
 		memset(mt->stringargs, 0x00, NUMMAPTHINGSTRINGARGS*sizeof(*mt->stringargs));
+		mt->special = 0;
 		mt->pitch = mt->roll = 0;
 
 		mt->type &= 4095;
@@ -1530,6 +1537,43 @@ static void ParseTextmapSectorParameter(UINT32 i, const char *param, const char
 		sectors[i].triggertag = atol(val);
 	else if (fastcmp(param, "triggerer"))
 		sectors[i].triggerer = atol(val);
+	else if (fastcmp(param, "action"))
+		sectors[i].action = atol(val);
+	else if (fastncmp(param, "stringarg", 9) && strlen(param) > 9)
+	{
+		size_t argnum = atol(param + 9);
+		if (argnum >= NUMSECTORSTRINGARGS)
+			return;
+		sectors[i].stringargs[argnum] = Z_Malloc(strlen(val) + 1, PU_LEVEL, NULL);
+		M_Memcpy(sectors[i].stringargs[argnum], val, strlen(val) + 1);
+	}
+	else if (fastncmp(param, "arg", 3) && strlen(param) > 3)
+	{
+		size_t argnum = atol(param + 3);
+		if (argnum >= NUMSECTORARGS)
+			return;
+		sectors[i].args[argnum] = atol(val);
+	}
+	else if (fastcmp(param, "repeatspecial") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_REPEATSPECIAL;
+	else if (fastcmp(param, "playerenter") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_ENTER;
+	else if (fastcmp(param, "playerfloor") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_FLOOR;
+	else if (fastcmp(param, "playerceiling") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_CEILING;
+	else if (fastcmp(param, "monsterenter") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_ENTERMONSTER;
+	else if (fastcmp(param, "monsterfloor") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_FLOORMONSTER;
+	else if (fastcmp(param, "monsterceiling") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_CEILINGMONSTER;
+	else if (fastcmp(param, "missileenter") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_ENTERMISSILE;
+	else if (fastcmp(param, "missilefloor") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_FLOORMISSILE;
+	else if (fastcmp(param, "missileceiling") && fastcmp("true", val))
+		sectors[i].activation |= SECSPAC_CEILINGMISSILE;
 }
 
 static void ParseTextmapSidedefParameter(UINT32 i, const char *param, const char *val)
@@ -1642,9 +1686,9 @@ static void ParseTextmapLinedefParameter(UINT32 i, const char *param, const char
 		lines[i].flags |= ML_NOTBOUNCY;
 	else if (fastcmp(param, "transfer") && fastcmp("true", val))
 		lines[i].flags |= ML_TFERLINE;
-	else if (fastcmp(param, "repeatspecial") && fastcmp("true", val))
-		lines[i].flags |= ML_REPEATSPECIAL;
 	// Activation flags
+	else if (fastcmp(param, "repeatspecial") && fastcmp("true", val))
+		lines[i].activation |= SPAC_REPEATSPECIAL;
 	else if (fastcmp(param, "playercross") && fastcmp("true", val))
 		lines[i].activation |= SPAC_CROSS;
 	else if (fastcmp(param, "monstercross") && fastcmp("true", val))
@@ -2219,7 +2263,7 @@ static void P_WriteTextmap(void)
 			fprintf(f, "notbouncy = true;\n");
 		if (wlines[i].flags & ML_TFERLINE)
 			fprintf(f, "transfer = true;\n");
-		if (wlines[i].flags & ML_REPEATSPECIAL)
+		if (wlines[i].activation & SPAC_REPEATSPECIAL)
 			fprintf(f, "repeatspecial = true;\n");
 		if (wlines[i].activation & SPAC_CROSS)
 			fprintf(f, "playercross = true;\n");
@@ -2403,6 +2447,34 @@ static void P_WriteTextmap(void)
 			fprintf(f, "triggertag = %d;\n", wsectors[i].triggertag);
 		if (wsectors[i].triggerer != 0)
 			fprintf(f, "triggerer = %d;\n", wsectors[i].triggerer);
+		if (wsectors[i].action != 0)
+			fprintf(f, "action = %d;\n", wsectors[i].action);
+		for (j = 0; j < NUMSECTORARGS; j++)
+			if (wsectors[i].args[j] != 0)
+				fprintf(f, "arg%s = %d;\n", sizeu1(j), wsectors[i].args[j]);
+		for (j = 0; j < NUMSECTORSTRINGARGS; j++)
+			if (wsectors[i].stringargs[j])
+				fprintf(f, "stringarg%s = \"%s\";\n", sizeu1(j), wsectors[i].stringargs[j]);
+		if (wsectors[i].activation & SECSPAC_REPEATSPECIAL)
+			fprintf(f, "repeatspecial = true;\n");
+		if (wsectors[i].activation & SECSPAC_ENTER)
+			fprintf(f, "playerenter = true;\n");
+		if (wsectors[i].activation & SECSPAC_FLOOR)
+			fprintf(f, "playerfloor = true;\n");
+		if (wsectors[i].activation & SECSPAC_CEILING)
+			fprintf(f, "playerceiling = true;\n");
+		if (wsectors[i].activation & SECSPAC_ENTERMONSTER)
+			fprintf(f, "monsterenter = true;\n");
+		if (wsectors[i].activation & SECSPAC_FLOORMONSTER)
+			fprintf(f, "monsterfloor = true;\n");
+		if (wsectors[i].activation & SECSPAC_CEILINGMONSTER)
+			fprintf(f, "monsterceiling = true;\n");
+		if (wsectors[i].activation & SECSPAC_ENTERMISSILE)
+			fprintf(f, "missileenter = true;\n");
+		if (wsectors[i].activation & SECSPAC_FLOORMISSILE)
+			fprintf(f, "missilefloor = true;\n");
+		if (wsectors[i].activation & SECSPAC_CEILINGMISSILE)
+			fprintf(f, "missileceiling = true;\n");
 		fprintf(f, "}\n");
 		fprintf(f, "\n");
 	}
@@ -2497,6 +2569,11 @@ static void P_LoadTextmap(void)
 
 		sc->friction = ORIG_FRICTION;
 
+		sc->action = 0;
+		memset(sc->args, 0, NUMSECTORARGS*sizeof(*sc->args));
+		memset(sc->stringargs, 0x00, NUMSECTORSTRINGARGS*sizeof(*sc->stringargs));
+		sc->activation = 0;
+
 		textmap_colormap.used = false;
 		textmap_colormap.lightcolor = 0;
 		textmap_colormap.lightalpha = 25;
@@ -2549,6 +2626,8 @@ static void P_LoadTextmap(void)
 		ld->sidenum[0] = 0xffff;
 		ld->sidenum[1] = 0xffff;
 
+		ld->activation = 0;
+
 		TextmapParse(linesPos[i], i, ParseTextmapLinedefParameter);
 
 		if (!ld->v1)
@@ -2593,6 +2672,7 @@ static void P_LoadTextmap(void)
 		mt->scale = mapobjectscale;
 		memset(mt->args, 0, NUMMAPTHINGARGS*sizeof(*mt->args));
 		memset(mt->stringargs, 0x00, NUMMAPTHINGSTRINGARGS*sizeof(*mt->stringargs));
+		mt->special = 0;
 		mt->mobj = NULL;
 
 		TextmapParse(mapthingsPos[i], i, ParseTextmapThingParameter);
@@ -5843,14 +5923,12 @@ static void P_ConvertBinaryLinedefTypes(void)
 			lines[i].blendmode = AST_FOG;
 			break;
 		case 2001: //Finish line
-			lines[i].activation |= SPAC_CROSS;
-			lines[i].flags |= ML_REPEATSPECIAL;
+			lines[i].activation |= (SPAC_CROSS|SPAC_REPEATSPECIAL);
 			if (lines[i].flags & ML_NOCLIMB)
 				lines[i].args[0] |= TMCFF_FLIP;
 			break;
 		case 2003: //Respawn line
-			lines[i].activation |= SPAC_CROSS;
-			lines[i].flags |= ML_REPEATSPECIAL;
+			lines[i].activation |= (SPAC_CROSS|SPAC_REPEATSPECIAL);
 			if (lines[i].flags & ML_NOCLIMB)
 				lines[i].args[0] |= TMCRF_FRONTONLY;
 			break;
diff --git a/src/p_spec.c b/src/p_spec.c
index 938c20123..0a80f52f1 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -2101,7 +2101,7 @@ static void K_HandleLapDecrement(player_t *player)
 
 static void P_LineSpecialWasActivated(line_t *line)
 {
-	if (!(line->flags & ML_REPEATSPECIAL))
+	if (!(line->activation & SPAC_REPEATSPECIAL))
 	{
 		line->special = 0;
 	}
@@ -5410,6 +5410,260 @@ void P_CheckMobjTrigger(mobj_t *mobj, boolean pushable)
 	P_CheckMobjSectorTrigger(mobj, originalsector);
 }
 
+static void P_SectorActionWasActivated(sector_t *sec)
+{
+	if ((sec->activation & SECSPAC_REPEATSPECIAL) == 0)
+	{
+		sec->action = 0;
+	}
+}
+
+static boolean P_AllowSpecialEnter(sector_t *sec, mobj_t *thing)
+{
+	if (thing->player != NULL)
+	{
+		return !!(sec->activation & SECSPAC_ENTER);
+	}
+	else if ((thing->flags & (MF_ENEMY|MF_BOSS)) != 0)
+	{
+		return !!(sec->activation & SECSPAC_ENTERMONSTER);
+	}
+	else if (K_IsMissileOrKartItem(thing) == true)
+	{
+		return !!(sec->activation & SECSPAC_ENTERMISSILE);
+	}
+
+	// No activation flags for you.
+	return false;
+}
+
+static boolean P_AllowSpecialFloor(sector_t *sec, mobj_t *thing)
+{
+	if (thing->player != NULL)
+	{
+		return !!(sec->activation & SECSPAC_FLOOR);
+	}
+	else if ((thing->flags & (MF_ENEMY|MF_BOSS)) != 0)
+	{
+		return !!(sec->activation & SECSPAC_FLOORMONSTER);
+	}
+	else if (K_IsMissileOrKartItem(thing) == true)
+	{
+		return !!(sec->activation & SECSPAC_FLOORMISSILE);
+	}
+
+	// No activation flags for you.
+	return false;
+}
+
+static boolean P_AllowSpecialCeiling(sector_t *sec, mobj_t *thing)
+{
+	if (thing->player != NULL)
+	{
+		return !!(sec->activation & SECSPAC_CEILING);
+	}
+	else if ((thing->flags & (MF_ENEMY|MF_BOSS)) != 0)
+	{
+		return !!(sec->activation & SECSPAC_CEILINGMONSTER);
+	}
+	else if (K_IsMissileOrKartItem(thing) == true)
+	{
+		return !!(sec->activation & SECSPAC_CEILINGMISSILE);
+	}
+
+	// No activation flags for you.
+	return false;
+}
+
+static void P_CheckMobj3DFloorAction(mobj_t *mo, sector_t *sec)
+{
+	sector_t *originalsector = mo->subsector->sector;
+	ffloor_t *rover;
+	sector_t *roversec;
+
+	activator_t *activator = NULL;
+	boolean result = false;
+
+	for (rover = sec->ffloors; rover; rover = rover->next)
+	{
+		roversec = rover->master->frontsector;
+
+		if (P_CanActivateSpecial(roversec->action) == false)
+		{
+			// No special to even activate.
+			continue;
+		}
+
+		if (P_AllowSpecialEnter(roversec, mo) == false)
+		{
+			boolean floor = false;
+			boolean ceiling = false;
+
+			if (P_AllowSpecialFloor(roversec, mo) == true)
+			{
+				floor = (P_GetMobjFeet(mo) == P_GetSpecialTopZ(mo, roversec, roversec));
+			}
+
+			if (P_AllowSpecialCeiling(roversec, mo) == true)
+			{
+				ceiling = (P_GetMobjHead(mo) == P_GetSpecialBottomZ(mo, roversec, roversec));
+			}
+
+			if (floor == false && ceiling == false)
+			{
+				continue;
+			}
+		}
+
+		activator = Z_Calloc(sizeof(activator_t), PU_LEVEL, NULL);
+		I_Assert(activator != NULL);
+
+		P_SetTarget(&activator->mo, mo);
+		activator->sector = roversec;
+
+		result = P_ProcessSpecial(activator, roversec->action, roversec->args, roversec->stringargs);
+		Z_Free(activator);
+
+		if (result == true)
+		{
+			P_SectorActionWasActivated(roversec);
+		}
+
+		if TELEPORTED(mo) return;
+	}
+}
+
+static void P_CheckMobjPolyobjAction(mobj_t *mo)
+{
+	sector_t *originalsector = mo->subsector->sector;
+	polyobj_t *po;
+	sector_t *polysec;
+	boolean touching = false;
+	boolean inside = false;
+
+	activator_t *activator = NULL;
+	boolean result = false;
+
+	for (po = mo->subsector->polyList; po; po = (polyobj_t *)(po->link.next))
+	{
+		polysec = po->lines[0]->backsector;
+
+		touching = P_MobjTouchingPolyobj(po, mo);
+		inside = P_MobjInsidePolyobj(po, mo);
+
+		if (!(inside || touching))
+			continue;
+
+		if (P_CanActivateSpecial(polysec->action) == false)
+		{
+			// No special to even activate.
+			continue;
+		}
+
+		if (P_AllowSpecialEnter(polysec, mo) == false)
+		{
+			boolean floor = false;
+			boolean ceiling = false;
+
+			if (P_AllowSpecialFloor(polysec, mo) == true)
+			{
+				floor = (P_GetMobjFeet(mo) == P_GetSpecialTopZ(mo, polysec, polysec));
+			}
+
+			if (P_AllowSpecialCeiling(polysec, mo) == true)
+			{
+				ceiling = (P_GetMobjHead(mo) == P_GetSpecialBottomZ(mo, polysec, polysec));
+			}
+
+			if (floor == false && ceiling == false)
+			{
+				continue;
+			}
+		}
+
+		activator = Z_Calloc(sizeof(activator_t), PU_LEVEL, NULL);
+		I_Assert(activator != NULL);
+
+		P_SetTarget(&activator->mo, mo);
+		activator->sector = polysec;
+
+		result = P_ProcessSpecial(activator, polysec->action, polysec->args, polysec->stringargs);
+		Z_Free(activator);
+
+		if (result == true)
+		{
+			P_SectorActionWasActivated(polysec);
+		}
+
+		if TELEPORTED(mo) return;
+	}
+}
+
+static void P_CheckMobjSectorAction(mobj_t *mo, sector_t *sec)
+{
+	activator_t *activator = NULL;
+	boolean result = false;
+
+	if (P_CanActivateSpecial(sec->action) == false)
+	{
+		// No special to even activate.
+		return;
+	}
+
+	if (P_AllowSpecialEnter(sec, mo) == false)
+	{
+		boolean floor = false;
+		boolean ceiling = false;
+
+		if (P_AllowSpecialFloor(sec, mo) == true)
+		{
+			floor = (P_GetMobjFeet(mo) == P_GetSpecialBottomZ(mo, sec, sec));
+		}
+
+		if (P_AllowSpecialCeiling(sec, mo) == true)
+		{
+			ceiling = (P_GetMobjHead(mo) == P_GetSpecialTopZ(mo, sec, sec));
+		}
+
+		if (floor == false && ceiling == false)
+		{
+			return;
+		}
+	}
+
+	activator = Z_Calloc(sizeof(activator_t), PU_LEVEL, NULL);
+	I_Assert(activator != NULL);
+
+	P_SetTarget(&activator->mo, mo);
+	activator->sector = sec;
+
+	result = P_ProcessSpecial(activator, sec->action, sec->args, sec->stringargs);
+	Z_Free(activator);
+
+	if (result == true)
+	{
+		P_SectorActionWasActivated(sec);
+	}
+}
+
+void P_CheckMobjTouchingSectorActions(mobj_t *mobj)
+{
+	sector_t *originalsector;
+
+	if (!mobj->subsector)
+		return;
+
+	originalsector = mobj->subsector->sector;
+
+	P_CheckMobj3DFloorAction(mobj, originalsector);
+	if TELEPORTED(mobj)	return;
+
+	P_CheckMobjPolyobjAction(mobj);
+	if TELEPORTED(mobj)	return;
+
+	P_CheckMobjSectorAction(mobj, originalsector);
+}
+
 #undef TELEPORTED
 
 /** Animate planes, scroll walls, etc. and keeps track of level timelimit and exits if time is up.
diff --git a/src/p_spec.h b/src/p_spec.h
index c8f5721e2..6ccb328cd 100644
--- a/src/p_spec.h
+++ b/src/p_spec.h
@@ -547,6 +547,7 @@ sector_t *P_PlayerTouchingSectorSpecial(player_t *player, INT32 section, INT32 n
 sector_t *P_PlayerTouchingSectorSpecialFlag(player_t *player, sectorspecialflags_t flag);
 void P_PlayerInSpecialSector(player_t *player);
 void P_CheckMobjTrigger(mobj_t *mobj, boolean pushable);
+void P_CheckMobjTouchingSectorActions(mobj_t *mobj);
 sector_t *P_FindPlayerTrigger(player_t *player, line_t *sourceline);
 boolean P_IsPlayerValid(size_t playernum);
 boolean P_CanPlayerTrigger(size_t playernum);
diff --git a/src/r_defs.h b/src/r_defs.h
index e5c6ea834..84b4e4993 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -371,6 +371,39 @@ typedef enum
 	SSF_ZOOMTUBEEND = 1<<16,
 } sectorspecialflags_t;
 
+typedef enum
+{
+	// Special action is repeatable.
+	SECSPAC_REPEATSPECIAL		= 0x00000001,
+
+	// When a player enters this sector.
+	SECSPAC_ENTER				= 0x00000002,
+
+	// When a player touches the floor of this sector.
+	SECSPAC_FLOOR				= 0x00000004,
+
+	// When a player touches the ceiling of this sector.
+	SECSPAC_CEILING				= 0x00000008,
+
+	// When an enemy enters this sector.
+	SECSPAC_ENTERMONSTER		= 0x00000010,
+
+	// When an enemy touches the floor of this sector.
+	SECSPAC_FLOORMONSTER		= 0x00000020,
+
+	// When an enemy touches the ceiling of this sector.
+	SECSPAC_CEILINGMONSTER		= 0x00000040,
+
+	// When a projectile enters this sector.
+	SECSPAC_ENTERMISSILE		= 0x00000080,
+
+	// When a projectile touches the floor of this sector.
+	SECSPAC_FLOORMISSILE		= 0x00000100,
+
+	// When a projectile touches the ceiling of this sector.
+	SECSPAC_CEILINGMISSILE		= 0x00000200,
+} sectoractionflags_t;
+
 typedef enum
 {
 	SD_NONE = 0,
@@ -396,6 +429,9 @@ typedef enum
 	CRUMBLE_RESTORE, // Crumble thinker is about to restore to original position
 } crumblestate_t;
 
+#define NUMSECTORARGS 10
+#define NUMSECTORSTRINGARGS 2
+
 //
 // The SECTORS record, at runtime.
 // Stores things/mobjs.
@@ -500,6 +536,12 @@ struct sector_t
 
 	// colormap structure
 	extracolormap_t *spawn_extra_colormap;
+
+	// Action specials
+	INT16 action;
+	INT32 args[NUMSECTORARGS];
+	char *stringargs[NUMSECTORSTRINGARGS];
+	sectoractionflags_t activation;
 };
 
 //