It comes with being here for over seventy days. Duke's gotten used to the idea that the laws of Terca Lumireis don't apply to all of the worlds, but the comment about learning magic does get a blink. "That - academic? - sounds more like mine. It can be learned, so long as someone wants to study, but the elements that someone is particularly good at vary for no known reason."

As for the Bastion itself - "It... is complicated. Nathaniel can explain it better - he's one of the people who is from this world, where they made the Bastion. The way I understand it is its a really big magical construct - collect Cores, which are giant shards, and it builds buildings, expands. Before your Briar showed up, none of us knew how to do anything with the field, but there was edible plants growing there enough for everyone to eat, at least."