[@Ryonara]
While I am not exactly appreciative of you going and looking things up from the MM, the info you have is indeed correct. In a fair fight, the party would stand no chance against an adult dragon. I'll have to withhold any further knowledge of the situation to myself as to not ruin the encounter.

Just... could you please not pull out the source material and use the raw mechanics information for metagaming? I trust that the plan of "living to fight another day" could have been formed from the storytelling alone.