My Story Hour has an example of how a dragon can exert tremendous influence and create plenty of danger for a group of PCs without even making an appearance. The dragon in question has been a part of the campaign since the beginning -- the PCs have met him at least twice. Someday, maybe, they will be able to take him out -- if they don't mind breaking local laws to do so. 
In the most recent episode, the dragon's agents posed a puzzle. I am curious to hear what people on the board would give as an answer...

In the most recent episode, the dragon's agents posed a puzzle. I am curious to hear what people on the board would give as an answer...