Muls in Dark Sun are a dwarf/human hybrid who are bred mainly for slave labor. This means not only are they as hardy as dwarves, but they also have the versatility of humans.
In Dark Sun, Dwarves get essentially deflavored while Muls get all the cool, "never say die" type skills. Dwarves get their beards taken away, and since they are in a metal-scarce world, they get their black smithing taken too. Dwarves are relegated to being engineers, which is cool for an npc, but not really useful for a player. Oh, and there aren't any Dwarven cities or fortresses. So no "Ironforge".
Dwarves do have a lame addition that is a holdover from the AD&D days of Dark Sun. Dwarves have a "obsession" of sorts that represents their tenacity. This is borderline useless and more of an individual role playing thing.
Dwarves do have a lame addition that is a holdover from the AD&D days of Dark Sun. Dwarves have a "obsession" of sorts that represents their tenacity. This is borderline useless and more of an individual role playing thing.
Muls on the other hand are an oppressed race who are literally bred for slavery. They have the same racial modifiers as dwarves and get to choose whether they select from human or Dwarven feats. I've never seen a player pick a Dwarf in Dark Sun, rather, they'll choose a Mul and pick from the Dwarf feats.
In the end, I kind of feel bad for Dwarves in Dark Sun, but at the same time, I don't because WOTC just made Muls much more attractive.