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So I'd assume that dragons live for a long time — at the very least, around 500 years or so, and that's just me guessing off the top of my head. There is a very clear distinction in terms of attacks and stats, however, between "adult" dragons and "ancient" dragons. When in its lifespan exactly does an adult dragon become classified as ancient? Is it when it's on the brink of death? Is it after a certain number of years? Is it once the dragon gains a certain amount of infamy, due to its terrible deeds or glorious renown? And does a dragon ever get so old that it's beyond ancient — as in, teeth falling out, dentures, bifocals, etc.?