“ Darklings are a kind of Halflings living in the sewer of medium to large cities.
Even though they smell badly and are quite dirty, Darklings are friendly and clever.
They try to limit the knowledge about their existence to only a small number of trustworthy persons, including player characters.
Darklings trade in information. Money, weapons and magical items have no value for them. This is why they hide beneath the sewer grates, listening to all that is said in the city above.”
“ A planet (or city, valley ect) where those who enter witness protection can escape old age and death itself, so they can live for centuries without aging-provided they maintain their cover perfectly. If they are outed by anyone or ever utter their true name, they age the number of years they have not aged since the day they entered witness protection (which might mean that they age centuries in seconds and crumble into dust and bone.)”
“ As they travel they notice a horrible rotten smell. As they travel it gets stronger and stronger forcing them to cover their noses and mouth less they choke on the horrible smell. Rotting animal carcass that has been ripped apart and tracks all over, covered in maggots.”