I'm not sure specifically as I haven't read it. It could be about a unique or rare character or event, as 'rara avis' means a rare bird in Latin and often is used to describe something unique in English.
I'm not sure specifically what the 'avis banks story' is as there could be many stories with that name. It could be a personal account, a fictional tale, or something related to a particular place or event named Avis Banks.
There were a few novels about the construction of a doomsday fortress that he could recommend. Among them were " Apocalypse Rebirth: Building a Fortress at the Beginning of 14.8 Billion "," Building a Super Fortress at the Beginning of the Apocalypse ", and " Building a Super Fortress at the Beginning of the Apocalypse ". These novels were all based on the apocalyptic setting and told the story of the protagonist building a fortress in the apocalypse. However, as for which novel was more worthy of recommendation, he needed to read and understand the plot and evaluation of these novels. Therefore, he could not give a specific recommendation.
I'm not sure. It might have some roots in truth, but it could also be a creation of the author's imagination. We don't have enough information to know for certain.