Try gulping backwards, that’s what my Daddy used to say. Daddy takes one hour, for the one who wants to enter, to build his own door. Then he quickly slips inside, but that would only work if the structure is still alive. Using traditional heuristics, policemen can spot any dead volcano -- as long as it never decides to trap them in. Is there no other way out? Take the police as an example. Policemen make good use of passive force. You may not like passivity, and I understand your point.