My current project is an arctic-inspired campaign setting, Overland.

I was just going to ban Dragonborn, since the Silver/White dragonborn could just ignore the cold, and I didn't want to ban colors piecemeal.

Then I remembered City of Heroes. They had epic archetypes that were hunted down by certain enemies of ha had special weapons.

So I made an enemy group dedicated to killing dragonborn, Drako Feyrero. They believe that the loss of dragons could be remedied if they just killed off the dragonborn. The cult is secretive, but widespread. They often join the local guard or act as enforcers for other groups to get close to dragonborn.

Plus, at the higher levels, they can go after the cult leader.

The dragonborn are allowed, but the group puts a dent in "I have cold resistance."

I'm looking at giving all Dragonborn extra benefits, so I don't hose the non-silver/white Dragonborn with the special foes.

Any other ideas or thoughts on this?