Dwarves
The Dwarves are an ancient and long-lived race of intelligent, mortal humanoids who believe themselves to have been created by Magnus Allfather and descendants of the other members of the Dwarven Pantheon, and therefore call themselves the Clans of Magnus, forming a largely isolationist society all throughout the Atlas Mountains which extends into the Depths.
Dwarves live significantly longer than humans (a particularly senatorial dwarf might be 200-250 years old) but are truly mortal, unlike their Elf neighbours, who often outlive them.
Origin
The Dwarves were created by Magnus Allfather to serve in the households of the Firstborn, the Dwarven Gods, of the "clay that bears the seed of life", in a toil which lasted a year and a day. They were his third creations, and therefore some religious scholars among their kind also use the term "Thirdborn" to refer to dwarven kind. The Dwarf gods who use the "Magnussun" patrynom collectively make up the Firstborn, and a stone race of giant dwarves who live in and protect Khaz Urheim are the Secondborn.
Dwarven recordkeeping is so meticulous that any dwarf born in the Clans of Magnus culture can expect to be able to trace their geneology back to this first generation of Dwarves. As a result, Clans of Magnus dwarves use the patronymic of whichever god their progenitors were originally set to serve, rather than the literal patronym of their father. Outside of the mainstream Clans of Magnus culture, this habit tends to break down, with dwarves using other surnames.
Culture
See: Clans of Magnus
Almost all dwarves (except for minor populations occurring mostly in The North and the Bastonian Hinterlands are part of the mainstream Clans of Magnus culture, but even those who aren't tend to form strongly ordered cultures focused around a single, usually secret, stronghold in a mountain, crevice, ravine, or other geological fortress.
Physical Attributes
Lifespan
Dwarves track closely with humans in terms of their initial growth and development; a similar nine-month gestational period, two years of infancy, three or four of toddlerhood, and an eventual maturation into a full adult around the age of 20. Their aging then progresses much more slowly. A dwarf is said to have reached his finest years as he enters his second century of life - that is, around the age of a hundred years. From there, a slow progression of middle-age carries the next century into biography, with the beginning of age-related decline at around 180-200 years old. If sufficiently protective of their own health, however, even an elderly dwarf can easily expect to live another hundred or hundred and fifty years; deaths in the middle 300s are "ripe old age", and in some extreme cases even final ages in the low 400s are not entirely unheard of, though considered remarkable.
Rocksense and Stone-Legs
Dwarves are possessed of natural affinities which make them suited for the exploration - and indeed heavy colonization and exploitation - of underground spaces. A dwarf will never become disoriented about their direction while underground and, while underground, are functionally always aware of the rough direction of north. They have a reasonable sense of their depth below ground. Dwarves can sense an earthquake or other large shift a few seconds before the actual effects are felt. Some dwarves have a natural talent for prospecting, able to smell and taste metals in the rock or in runoff, and thereby "hound" for ores. While this last quality is not universal, it is highly prized.
Darkvision
Dwarves are adjusted to a life lived in "less than starlight" and can see up to 100m in utter darkness, though they cannot see colour in such a condition. Because of the limitations of this ability, they still prefer to illuminate spaces when possible, but it remains an essential survival skill and even, at times, a useful advantage.
Alcohol Dependence
Dwarves have a higher tolerance for alcohol intoxication than humans and effectively cannot become intoxicated by most beers, wines, or liquors, only risking intoxication when consuming fortified beverages or distilled spirits. However, these weaker beverages (especially the cultural favourites mead and ale) serve important metabolic functions for dwarves. A dwarf who is not able to consume at least a few flagons of a weak alcoholic beverage daily will become irritable within the day. Within a week, they begin to lose immune function and become more susceptible to diseases, fatigue, and exhaustion. Within a fortnight without consumption of alcohol, assuming they are not otherwise ill, they will become febrile, delusional, and debilitatingly fatigued, usually leaving them bedridden. Dwarven explorers often carry strong spirits that they water down in-situ with foraged water specifically to avoid these complications.
Spiritual and Mental Attributes
Dwarven Rhythm
Dwarves have an exceptionally precise sense of the passage of time as an innate ability. In addition to its utility in general timekeeping (five dwarves placed in lightless isolation from each other will continue to function in a daily rhythm of life that deviates from the solar day at a rate of less than one hour per month), this innate ability makes dwarves natural musicians and provides boons in any situation where groups of dwarven characters have to act together in time; from musical performances to group labour, and even enabling them to eschew signalling when forming plans based on adherence to a timetable.