My players have wound up bringing an ancient silver dragon to defend a town being attacked by a young red dragon. Of course the ancient silver dragon would beat the young red dragon solo, unless I'm missing something. My question is how do I run this encounter in a fun way without railroading the players (I originally wanted them to fight the dragon) and while staying accurate to what would logically happen?
The players do need to have some involvement in the actual fight, because they were the ones who started it.
My best idea at the moment is to have the players on damage control, putting out the fires and such, but I'm still not sure how to run that.