Because the dragons were being used and bred for war, the were made to reach maturity very quickly. Newborn dragons progress from wyrmlings to adults in about a decade. Thus, it is very uncommon to encounter any dragon of less than adult age. Also, dragons do not stop growing, so it is theoretically possible to have older and more powerful dragons than Great Wyrms. This is very rare, as they usually die in conflict with each other.
Dragons are not a very numerous race, especially since dragons usually only have one or two offspring at a time. Mortality rates are very high for their offspring, as they are usually looking for food and/or territory, which must be either taken from people or other dragons. The young that do survive tend to be the more intelligent offspring.
When the gods were forced from the world, their direct control of the dragons was destroyed. Most of the dragons continued in their roles for the rest of the war, but they were no longer compelled to obey. This proved a major problem for the evil armies, since the evil dragons began carving out their own territories and fighting each other, while the good dragons continued to aid their allies. This continues today, and good dragons will aid others who have similar goals while evil dragons will only help themselves.
The following is a brief description of the various dragons and their roles they played. They are listed from most to least powerful for each alignment. (The number in brackets represents their power ranking when compared to other dragons of similar age.)