What if you lived in a cave and drank stalactite water?
Dwarves are a synthetic species created by dragons sometime during the kobold slave revolts. Presumably they were intended to replace kobolds but were abandoned pretty early on in their development when most dragons left to live in the realms of magic.
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Dwarves are a subterranean race, preferring cold, humid, and dark environments. Like kobolds they are a constructed race and as such their biology is tailored to a specific environment. Their eyesight is not good for instance, as there is little light in caves, but their hearing, spatial awareness, and mechanoreception are all excellent, though their hearing is most acute for deep sounds and they are actually less perceptive of high pitch sounds than other species.
In appearance dwarves are most similar to humans, though they have rougher, almost scaly skin around their hands, forearms, feet, and lower legs. They are shorter as well, generally being around 5 feet in height. Young dwarves are very unlike humans though as they age they generally become more and more similar, though the rate at which this change happens may be quite slow depending on the population of dwarves. Usually by the time they are 50 they have started to develop a beard and most of the shin on their face and chest will have softened and become smoother. By the time they are 75 their 2nd set of eyelids will have been reabsorbed completely and most of their remaining adolescent traits have more or less arrived at their final state of softening.
The dwarven lifecycle is an unusual one