Issue InvalidOperationException: There was an error generating the XML document.

[TheMadRed]

This might be my strangest crash yet. I'm on Year 2 Fall 5th and every time I go to sleep the game try's to save and I get the following error;

17:59:02	ERROR	game	InvalidOperationException: There was an error generating the XML document. ---> InvalidOperationException: The type StardewValley.Monsters.RockGolem was not expected. Use the XmlInclude or SoapInclude attribute to specify types that are not known statically. at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write100_NPC(String n, String ns, NPC o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write112_Farm(String n, String ns, Farm o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write188_GameLocation(String n, String ns, GameLocation o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write280_SaveGame(String n, String ns, SaveGame o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write281_SaveGame(Object o) --- End of inner exception stack trace --- at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id) at SpaceCore.Patches.SaveGamePatcher.SerializeProxy(XmlSerializer serializer, XmlWriter origWriter, Object obj) in C:\Programming\StardewValley\ModSource\SpaceCore\Patches\SaveGamePatcher.cs:line 401 at StardewValley.SaveGame+<getSaveEnumerator>d__90.MoveNext_PatchedBy<spacechase0.SpaceCore>(<getSaveEnumerator>d__90 this) at StardewValley.SaveGame.<>c__DisplayClass88_0.<Save>b__0() at System.Threading.Tasks.Task.InnerInvoke() at System.Threading.Tasks.Task.<>c.<.cctor>b__277_0(Object obj) at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state) --- End of stack trace from previous location --- at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
17:59:02	ERROR	SMAPI	An error occurred in the overridden update loop: InvalidOperationException: There was an error generating the XML document. ---> InvalidOperationException: The type StardewValley.Monsters.RockGolem was not expected. Use the XmlInclude or SoapInclude attribute to specify types that are not known statically. at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write100_NPC(String n, String ns, NPC o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write112_Farm(String n, String ns, Farm o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write188_GameLocation(String n, String ns, GameLocation o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write280_SaveGame(String n, String ns, SaveGame o, Boolean isNullable, Boolean needType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterSaveGame.Write281_SaveGame(Object o) --- End of inner exception stack trace --- at StardewValley.SaveGame.Save()+MoveNext() in stardewvalley\Farmer\Farmer\SaveGame.cs:line 416 at StardewValley.Menus.SaveGameMenu.update_PatchedBy<spacechase0.SpaceCore>(SaveGameMenu this, GameTime time) at StardewValley.Menus.ShippingMenu.update(GameTime time) at StardewValley.Game1._update(GameTime gameTime) at StardewValley.Game1.Update(GameTime gameTime) at StardewModdingAPI.Framework.SCore.OnPlayerInstanceUpdating(SGame instance, GameTime gameTime, Action runUpdate)

I have no idea what's causing this so I hope somebody here does, let me know if you need to see the full log and I'll post the link