“ 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.”
“ A modern kingdom still strictly adheres to ancient traditions due to their long forgotten deity getting annoyed at the moral decay, appearing as an AI Singularity and forcefully correcting everything it sees as morally wrong. As such, even though the weapons and technology have improved, the culture hasn't.”
“ A vicious murder happens in a town that the party happens to pop in at. Under heavy suspicion as they are strangers, the party is forced to discover the perpetrator or have their reputations blackened, especially as more and more murders occur in the town, and mysteriously stop and restart when the party leaves to go kill off that evil necromancer who kidnapped the princess.
The only problem is that a demon, possessing one of the party, is the perpetrator. And the demon makes no signs that its living in the PC's head.
In fact, for all the party knows (except for the possessed person's), their companion is an evil murderer.
Do they try and execute their friend as he's a vicious murderer, and no evidence points to demonic posession? Or do they flee town with him, trusting him, and have their reputations destroyed?”