diff --git a/src/gamedata/g_mapinfo.h b/src/gamedata/g_mapinfo.h
index 30e85bd39..85f649341 100644
--- a/src/gamedata/g_mapinfo.h
+++ b/src/gamedata/g_mapinfo.h
@@ -473,6 +473,7 @@ enum ESkillProperty
 	SKILLP_SlowMonsters,
 	SKILLP_Infight,
 	SKILLP_PlayerRespawn,
+	SKILLP_SpawnMulti,
 };
 enum EFSkillProperty	// floating point properties
 {
@@ -516,6 +517,7 @@ struct FSkillInfo
 	int RespawnLimit;
 	double Aggressiveness;
 	int SpawnFilter;
+	bool SpawnMulti;
 	int ACSReturn;
 	FString MenuName;
 	FString PicName;
diff --git a/src/gamedata/g_skill.cpp b/src/gamedata/g_skill.cpp
index c47f5d2f1..5963dc878 100644
--- a/src/gamedata/g_skill.cpp
+++ b/src/gamedata/g_skill.cpp
@@ -76,6 +76,7 @@ void FMapInfoParser::ParseSkill ()
 	skill.RespawnLimit = 0;
 	skill.Aggressiveness = 1.;
 	skill.SpawnFilter = 0;
+	skill.SpawnMulti = false;
 	skill.ACSReturn = 0;
 	skill.MustConfirm = false;
 	skill.Shortcut = 0;
@@ -192,6 +193,10 @@ void FMapInfoParser::ParseSkill ()
 				else if (sc.Compare("nightmare")) skill.SpawnFilter |= 16;
 			}
 		}
+		else if (sc.Compare ("spawnmulti"))
+		{
+			skill.SpawnMulti = true;
+		}
 		else if (sc.Compare("ACSReturn"))
 		{
 			ParseAssign();
@@ -395,6 +400,8 @@ int G_SkillProperty(ESkillProperty prop)
 
 		case SKILLP_PlayerRespawn:
 			return AllSkills[gameskill].PlayerRespawn;
+		case SKILLP_SpawnMulti:
+			return AllSkills[gameskill].SpawnMulti;
 		}
 	}
 	return 0;
diff --git a/src/playsim/p_mobj.cpp b/src/playsim/p_mobj.cpp
index fb0c661ac..56fcf47ea 100644
--- a/src/playsim/p_mobj.cpp
+++ b/src/playsim/p_mobj.cpp
@@ -5354,7 +5354,6 @@ AActor *FLevelLocals::SpawnPlayer (FPlayerStart *mthing, int playernum, int flag
 	return mobj;
 }
 
-
 //
 // P_SpawnMapThing
 // The fields of the mapthing should
@@ -5367,6 +5366,8 @@ AActor *FLevelLocals::SpawnMapThing (FMapThing *mthing, int position)
 	int mask;
 	AActor *mobj;
 
+	bool spawnmulti = G_SkillProperty(SKILLP_SpawnMulti) || multiplayer;
+
 	if (mthing->EdNum == 0 || mthing->EdNum == -1)
 		return NULL;
 
@@ -5446,6 +5447,10 @@ AActor *FLevelLocals::SpawnMapThing (FMapThing *mthing, int position)
 		{
 			mask = MTF_COOPERATIVE;
 		}
+		else if (spawnmulti)
+		{
+			mask = MTF_COOPERATIVE|MTF_SINGLE;
+		}
 		else
 		{
 			mask = MTF_SINGLE;