She nods. "Nobody actually knows why casting is dangerous to start with, just that it is; Bar can loan you books about it if you want to know what some of the theories are. When you start, and for about the first month if you're practicing regularly, every spell you cast will be a miscast, which means that it will act the way it should for the first two days or so, and then it'll start acting strange, and then sometime on the third day it'll break on its own if it hasn't been broken manually. If it breaks on its own, that'll kill you; again, I don't know why. Your danger sense will warn you about miscasts, though. It usually takes about three or four months of practice, and I've never heard of it taking longer than six months, to get to the point of never having miscasts, and then they'll never happen again after that. What I told you about breaking spells when we first met applies here, too; the most important thing to know is that a spell cast on a person or animal or droid can't be broken except by killing them. It's traditional for the first person a new mage casts a spell on to be themselves; the spell forms I'll be giving you can be used together to let you see magic - any kind, mine and yours both - and that's the traditional first spell for a new mage to cast on themselves."