A Deity of some sort has unleashed a plague of bookworms or something like that in the area. Almost all spellbooks are destroyed, along with bardic and historical books.
“ In a miltaristic nation, the ownership of proper (improvised don't count) weapons and armor is mandatory for all citizens under penalty of inprisonment or death.”
“ The PCs are accosted in a major city containing at least one famous fortuneteller / prophet of the future. They are informed that their as-yet-unborn child will (insert terrible evil), and that, although they are very sorry, the PC must be executed to keep this from happening.”
“ There is a certain kind of silver-coloured spider who's bite injects an addictive drug into the person that creates a sense of euphoria. Once bitten the PC has a 50% chance of being addicted to the spider's bite and will carry it around with him or her.Long term use leads to serious injury or death.At first the PC will just seem a bit slower or sleepier then normal.”
