It goes without saying that anyone who does not like spoilers and hasn’t read this book yet should probably NOT read this answer.
There were, by the end of the book, four possible outcomes. One: Illien himself could somehow be fixed/retrieved/healed and become what he was meant to be. I considered that a) unlikely and b) out of character. When the answer to any question is b), it’s pretty much impossible without a ground up re-write. If readers consider something out of character, I have to live with that - but if I, as the writer, think it’s out of character, it kind of dies on the page. I can’t move forward.
The second outcome was that Kaylin herself could claim the tower. I could see that as much more distinct possibility; it would alter the whole feel of these books, because the Tower and the fiefs could not be a part-time endeavor, and she wasn’t likely to remain a Hawk if she was also a reluctant fieflord. But it is something she would do, or would try to do, if the situation was dire enough. It’s entirely within character, because sometimes her ambitions exceed her abilities. She’s not terribly old, and her experience, while deep, is not broad.
That left two other possibilities: Severn and Tiamaris.
If I had fully realized what needed to occur in the Tower before I started writing the book, I might have arranged the story in an entirely different way; as it was, Nightshade could not remain to take the Tower itself (he understood what had to occur) because he was already the lord of his Castle, itself a similar building.
When writing a series where events have effects but the characters are continuing characters, severely changing the entire existence of one of them adds both depth and hideous complication.
Severn, like Kaylin, might see the need to take the Tower, although he would take it for different reasons than Kaylin. His concerns are not as broad as hers. If he thought it would save Kaylin’s life, he could do it.
I don’t always know in advance what will happen. I knew, within these parameters of the possible, what could happen. Tiamaris, however, wanted what the Tower signified in a way that made perfect sense for his character, and he wanted it in a way that Kaylin couldn’t. In fact, Kaylin did mean to accept the responsibility of the Tower, and Tiamaris would not allow this, because he understood everything: what it would mean for him, what he could do, and what level of commitment was required.
My favorite part of Silence, in fact, is his speech after he knocks Kaylin out of the circle: It’s not enough to do something out of a sense of guilt. It’s not, it’s never, enough to do something to avoid boredom. Not when it requires both desire, intent and commitment.
Dragons have hoards. I’ve known this about them since the Arkon first appeared on the page. Tiamaris had not chosen his. There was literally nothing he wanted, besides knowledge, that could consume the whole of his devotion in that way. But the journey through the Tower, past and present, and what the Tower might signify in terms of rulership, etc., was not meant for anything less, in his humble opinion. And yes, it’s the Dragon variant of humble, which means not humble at all.
It’s not love at first sight - but it’s possibly the closest analogy.