Take a trip?
Nina was stunned at first, then she understood what was going on.
She thought about the whole incident and the actions she and Sherry took before and after the appearance of the strange object that looked like "living steel," and realized that it was perfectly normal for the Knowledge Guards to be cautious—any incident involving a Transcendent invasion must be investigated to the fullest extent to encompass all people and objects that might have been contaminated, which was an ironclad rule of the Guarders.
While on the ship, Fenna would often talk about her daily work as a Judge, which included many rules of the Guarders, and according to Uncle Duncan's usual sayings—it was these strict, almost harsh "rules" that ensured the survival of the City-State in the Deep Sea Era, and ensured most ordinary people could still live relatively peaceful days in this dangerous world.