Forgery = an illegal copy of a document, painting, etc. or the crime of making such illegal copies: These banknotes are forgeries. He increased his income by forgery. It has nothing to do with the act of forging a waepon or armor.

Did you ment to say hook, because a urchin is a street kid or a porcupine.

It's the fifth time that you use their insted of there. In this case it shuold have been "There are six basic classes..."