The Prince and his lovely little human sat in the library for hours as they looked through book after book for the right information. To his surprise, Yrsula had found a lot of blueprints - just not to ships. They were of old magic that used to make castles and homes function modernly.
There were plans and sigils for water pipes, light sources, and even designs for furniture that mimicked much of what was in the castle. All of them were useful, and so he and Yrsula made sure to keep them in neat piles for reference later.
If he..no... if they could evolve the humans into a city, restore the castle, and cultivate more magic, he'd feel much better about his position in this war. For now it was best to stay quiet and pick up all the skills he could.
"Master," Yrsula piped up from the desk where she had a book opened wide to a double-paged display of a ship.