Imagine a person wearing a cloak of invisibility flying a flying beast (e.g. winged horse, gryphon) which was also wearing a cloak of invisibility.
Small identical wooden or metal discs with a strange pattern engraved upon them (do not appear to be coinage). The discs can be found all over the continent; a farmer typically overturns several dozen when ploughing a field. Though they are unnaturally hard to break, they have no known use and are widely used as good-luck charms: almost all households would have them on the doors and on mantle pieces; many people carry one or more on them, bound on to a belt, necklace or sewn on to their clothes.
The size and number of knots in hair, tied around neck, or hanging from belt could signify family, importance, worship, guild affiliations. Being able to translate the meaning of the size and placement of knots can give you a a large understanding of who somebody is.
May be used in a more barbaric society. Where in cities peoples clothes and crests show who they are, barbarians have no need for this so use knots.