Error

Exception from asynchronous event: System.TypeInitializationException: An exception was thrown by the type initializer for AlienRace.HarmonyPatches ---> System.NullReferenceException: Object reference not set to an instance of an object
  at AlienRace.HarmonyPatches+<>c__DisplayClass0_0.<.cctor>b__0 (AlienRace.ThingDef_AlienRace ar) [0x00000] in <filename unknown>:0
  at System.Collections.Generic.List`1[AlienRace.ThingDef_AlienRace].ForEach (System.Action`1 action) [0x00000] in <filename unknown>:0
  at AlienRace.HarmonyPatches..cctor () [0x00000] in <filename unknown>:0
  --- End of inner exception stack trace ---
  at (wrapper managed-to-native) System.Runtime.CompilerServices.RuntimeHelpers:RunClassConstructor (intptr)
  at System.Runtime.CompilerServices.RuntimeHelpers.RunClassConstructor (RuntimeTypeHandle type) [0x00000] in <filename unknown>:0
  at Verse.StaticConstructorOnStartupUtility.CallAll () [0x00000] in <filename unknown>:0
  at Verse.PlayDataLoader.<DoPlayLoad>m__80F () [0x00000] in <filename unknown>:0
  at Verse.LongEventHandler.ExecuteToExecuteWhenFinished () [0x00000] in <filename unknown>:0
Verse.Log:Error(String)
Verse.LongEventHandler:RunEventFromAnotherThread(Action)
Verse.LongEventHandler:<UpdateCurrentAsynchronousEvent>m__84C()