Quote Originally Posted by AslanCross View Post
Dragons should always fight on their own terms. They have two primary advantages that the PCs are likely going to have to prepare for if they expect the battle:

1. Flight. Never put the dragon in an environment where its flight is negated. As such, while the cliche of the dragon in the cave comes from the lovable tradition of The Hobbit, where was Smaug's battle fought? In the sky, with a lot of flying room. Bilbo didn't fight Smaug in his own lair. (So yeah, I really hate the "fight the sleeping dragon in its lair" cliche.)
Just to expand on this, I'd like to point out how little space is required to accomplish this task, in terms of cave sizes. Low-CR dragons can easily have lairs made by their parents that are large enough to navigate without issue. For mid-high CR dragons, it'd be harder, but then, they'd probably focus on having a roomy 'front yard'(red dragons would have an entrance that opened up onto the volcano's top, for instance) and secret escape pathways.