I would absolutely love to see an outbreak of red-cough throughout the clans. It has never been properly introduced (Except in Moth flight's Vision, which was a very long time ago.) So lots of cats would die off because medicine cats wouldn't know the cure for it. Then there's another idea that SkyClan could bring a new disease into the clans (Since it's been at least 40-60 years from their exile.) Like!!! Erin Hunter!!! What are you doing with your opportunities??