The blackboard of the middle ages
A brightly colored ink that hardens the skin.
A small, ordinary looking red pouch that deters all but the most skilled thieves.
This thick sauce, usually a condiment on the platters of the rich, has found a niche in the equipment of thieves.
Magic is like alcohol, the more that is used, the more it causes a hangover later on and the less judgement one has when using it. If one waits a while after casting a spell, things "detoxify." A cantrip or two is like a sip of weak beer, whilst a large creation spell is like a bottle of vodka. Cast something too big and you can die from magic intoxication.