“ If you want to add a 'supernatural' touch to your campaign, define the rules of magic and the universe. Make your players comfortable with those rules. Then your new supernatural creatures must then break those rules.”
“ Elves are not actually aloof. They are actually extremely family-based and insular, and often intermarry inside their families, making them uncomfortable around those not of their family. Therefore, they shield themselves behind pretended aloofness and coldness until they are comfortable in others' company.”
“ Under the sewers of a large town ancient burial chambers are discovered. If the PCs investigate they fill find that a pale white flowers grows amongst the graves, in the dark.
How do they survive without light? What is their origin? Why in a burial chamber and not just in any old cave?
Can they be sold or do they have any special quality at all? It is up to the PCs to discover.”