Big, scaley and toothy. Fond of treasure, although who isn’t? Not particularly good to eat.
Pray you don’t have the fate of running into one in a bad mood. Most tend to avoid chowing down on too many people, but a few… well, just watch out for them.
Dragons require a high level of ambient magic for metabolic purposes, and quickly lapse into hibernation (and, as seen on Erff, eventual evolution) in the absence thereof.
Regardless of elemental affiliation or scale shade, all dragons may be considered morally neutral. (Not unlike most Sentients, funnily enough.) Individual dragons may well have their own codes of ethics, but most of them are too lenient about things like occasionally munching on Sentient beings to be purely good and too concerned about the world around them (if for no other reason than to preserve their holdings and their continued ability to tap into rich veins of magic) to be truly evil.
Female dragons are large and powerful, but have somewhat muted colors of scale and less dramatic horns and/or frills. Males are smaller but much more flamboyant in nature; the extent of their mating-related “plumage” (and the accompanying dance movements) puts even the most exotic bird species to shame. Given that dragons are sentient and thus inclined to rather enjoy mating, this makes a certain degree of sense.
Dragons are mammalesque in nature, much like their Erffly cousins; they gestate their young for a time and then lay them as eggs before the fetus’s developing body would no longer comfortably fit past the mother’s hip bones. Although young dragons emerge from the shell ready to eat solid food and indeed fend for themselves in all ways if necessary, some mother dragons do nurse; they secrete a milk-like fluid from their bellies which collects in special grooves in their scales. The benefits of nursing a child that is already capable of eating solid food are somewhat muted, but like in mammals, this allows the mother to pass on antibodies and trace nutrients to her offspring, as well as being something of a bonding experience. (Dragons are notoriously lacking in the bonding department otherwise.)