diff --git a/extras/conf/udb/Includes/SRB222_things.cfg b/extras/conf/udb/Includes/SRB222_things.cfg
index d5af8fb90d86473a1ffb0fb49877e6dd6ddedeb0..e5bec6d3a3ea1f2235e3fa06d7d6e91c7ea8dff9 100644
--- a/extras/conf/udb/Includes/SRB222_things.cfg
+++ b/extras/conf/udb/Includes/SRB222_things.cfg
@@ -3764,6 +3764,12 @@ udmf
 			sprite = "PYREA0";
 			width = 24;
 			height = 34;
+			arg0
+			{
+				title = "Start on fire?";
+				type = 11;
+				enum = "noyes";
+			}
 		}
 		137
 		{
diff --git a/src/p_mobj.c b/src/p_mobj.c
index 0652967d7b0066b52ccedfc8ce70bb47bad68c01..7c44ae8da3fb10f5df174070de612375f97d80a9 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -12924,8 +12924,8 @@ static boolean P_SetupSpawnedMapThing(mapthing_t *mthing, mobj_t *mobj, boolean
 		}
 		break;
 	case MT_PYREFLY:
-		//start on fire if Ambush flag is set, otherwise behave normally
-		if (mthing->options & MTF_AMBUSH)
+		//start on fire if args[0], otherwise behave normally
+		if (mthing->args[0])
 		{
 			P_SetMobjState(mobj, mobj->info->meleestate);
 			mobj->extravalue2 = 2;
diff --git a/src/p_setup.c b/src/p_setup.c
index 9ef53911057d52e4031f465d9f2a27a637d57d17..03a7cf564b00b4becfc4d7ba55709f50e795cd50 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -4896,6 +4896,9 @@ static void P_ConvertBinaryMap(void)
 		case 135: //Pterabyte Spawner
 			mapthings[i].args[0] = mapthings[i].extrainfo + 1;
 			break;
+		case 136: //Pyre Fly
+			mapthings[i].args[0] = !!(mapthings[i].options & MTF_AMBUSH);
+			break;
 		case 502: //Star post
 			if (mapthings[i].extrainfo)
 				// Allow thing Parameter to define star post num too!