Another half-shrug. "I might be working on it for the rest of my life here. I'll do it until I stop getting better, then I'll do it to keep in practice." After a pause, he adds, "It's getting close on time to return to the castle. When we get there, we might as well go to one of the practice rooms. You can show me what you can do with ice... if you're not too tired."

He can only assume that the fire came to him because wights were much on his mind when he was first brought here -- wights, and what he needed to do to fight them. A wall of ice is like enough to keep them out: it has for thousands of years, with what is rumored to be the right wards. But it will take fire to kill them.