"If you're using a weapon, I doubt you're merely sparring, so...it's all right to fight unfairly - a hit to the knees can stun or disable them if you've enough strength."

There was a pause to think. Enoch didn't like to think much about fighting with humans, and it was a matter of putting something that seemed common sense or intuition into words...

"...Elbows or hands are good targets, as well, if you can hit them."