Hidden in the Gozwin Mountains, Waterdark is the fortress of the order that cut every dragon-bond in Adron at the Severing, four centuries ago. Its founder was Kareshi, and the order has kept his name a great deal longer than it has kept his numbers. Few Nagashi can hold water and darkness in one working; the order has never been more than a few.
The fortress looks empty unless you know what to look for, which suits an order that is quieter and smaller now than it was the night it ended the Wyrmward. What it is for, by the account Adron has held for four hundred years, is watch. The dark leyline runs under the Gozwin range, and the order keeps to it so the souring that turned the dragon-bonds can never start again. That is the answer the kingdom is given. Whether it is the whole answer is a question no one has put to the order's face.