diff --git a/source/games/duke/src/savegame.cpp b/source/games/duke/src/savegame.cpp
index bdc7c4e2a..49e0f582f 100644
--- a/source/games/duke/src/savegame.cpp
+++ b/source/games/duke/src/savegame.cpp
@@ -296,7 +296,11 @@ void DDukeActor::Serialize(FSerializer& arc)
 FSerializer& Serialize(FSerializer& arc, const char* keyname, Cycler& w, Cycler* def)
 {
 	static Cycler nul;
-	if (!def) def = &nul;
+	if (!def)
+	{
+		def = &nul;
+		if (arc.isReading()) w = {};
+	}
 	if (arc.BeginObject(keyname))
 	{
 		arc("sector", w.sector, def->sector)
@@ -313,7 +317,11 @@ FSerializer& Serialize(FSerializer& arc, const char* keyname, Cycler& w, Cycler*
 FSerializer& Serialize(FSerializer& arc, const char* keyname, AmbientTags& w, AmbientTags* def)
 {
 	static AmbientTags nul;
-	if (!def) def = &nul;
+	if (!def)
+	{
+		def = &nul;
+		if (arc.isReading()) w = {};
+	}
 	if (arc.BeginObject(keyname))
 	{
 		arc("lotag", w.lo, def->lo)
@@ -326,7 +334,11 @@ FSerializer& Serialize(FSerializer& arc, const char* keyname, AmbientTags& w, Am
 FSerializer& Serialize(FSerializer& arc, const char* keyname, animate& w, animate* def)
 {
 	static animate nul;
-	if (!def) def = &nul;
+	if (!def)
+	{
+		def = &nul;
+		if (arc.isReading()) w = {};
+	}
 	if (arc.BeginObject(keyname))
 	{
 		arc("sector", w.sect, def->sect)