Just a question: if alchemists, blacksmiths, phisicians etc can only use weapons which don't require a permit... why do they need a permit??? Just in order to state they are members of their guilds?
Guard A: Hey B, you see the guy in fancy robes with arcane signs, who is muttering a spell and telling his friends he is a mage?
Guard B: Yes
Guard A: Can you please go ask his him his mage permit?
Guard B: Of course pal!
(Three minutes later B comes back turned into a frog)
Guard B: RIBBIT!!!
Guard A: I'll take it as a "yes"
