I have the Revised Edition of Dungeon Quest. I remember playing the original edition, and the dragon deck automatically shuffles if there are no heroes inside the treasure chamber.
But I can't find anything in the revised rules for when the dragon deck shuffles. Reading the "Dragon Rage" card, it seems the deck shuffles whenever someone draws that card and waked the dragon. In the original version, drawing that card forced everyone out of the treasure chamber, and that caused the deck to reshuffle as a side effect.
So in the revised edition, does the dragon deck shuffle when there are no heroes in the treasure chamber? Or only when someone is unlucky enough to wake the dragon?