It's been said that there are all kinds of rich assholes' safety places, built if the world goes to shit. They'll run there while apocalypse goes on outside. Authors have referred to this in novels that I've read, saying in notes that such places exist. Problem is, rich assholes are too stupid to know that they can't stay there forever; even the best designs are going to run out at some time, apart from being rats locked up, who, presumably will turn against themselves like rats do. Elsewise they'll have to come out at some point, and hopefully be strung up or torn apart by the struggling masses, which sounds good to me. It is said that the assholes have no interest in saving the world, only preparing for calamity and surviving it. Should this come to pass they'll find it doesn't work like that. Having obscene wealth is only good while the world goes on in some normal fashion, with the underclasses toiling away and serving them.

If these people are smart enough to get in all one has to do is wait until they come out and it is a shooting gallery. They will have a lot of guns but will only have one point of view to shoot from. They will all be computer operated and have their own power source. They will have gold and cash. All thee things will do them no good if they cannot get out and retake control, which they will not unless the stupid rule without them. One does not need to open the place all they need to do is weld it so it cannot be opened.