Is faking your death illegal

With intent to defraud is an obvious answer. Perhaps how you do it mitigates other criminal acts. If you are using a corpse, God forbid, yes. If your intent is to get a death certificate yes, that’s a false instrument. But if you just went missing and someone petitioned the court for a declaration of death (usually missing 7 years) no. Fact is these days it’s pretty hard to hide.