How quickly can a ship be built — or a fleet? I’m thinking of course about Euron’s new Ironborn fleet on the show, but also of Cersei’s dromonds in the books.

Ships take time to build, and one of the genuine pillars of Braavos’ strength is that its Arsenal can build a war galley in a day thanks to standardized parts and assembly line production.

In AFFC, it takes about three weeks for King’s Landing to build three dromonds, so building an entire new Royal Fleet of 100 ships from scratch would take two years. Presumably the fleet that Stannis built in the nine months between the fall of King’s Landing and the assault on Dragonstone was smaller than 100 ships.