Spying on Afena and Rudsis in his dreams, Treni knew that they were, very likely, already in Crown. Her suspicions were confirmed when, looking down into the city from the top of her pyramid, she saw an inn window light up with her magically enhanced sight.
"And here you are," she said out loud to herself. "That will be you, Afena, trying to see if I leave my quarters invisibly. But did Rudsis stay with you? I doubt it."
She knew how things would look to Afena right now. Everything would seem as if bathed by the light of the sun, but there would be an incandescent cube of light on top of the pyramid. The Inarenta would not be able to see through the cube of light, because magic showed as a shining mass. Within that cube, Treni was able to use as much magic as she wanted, and Afena would not notice it.