Underdwarves

Underdwarves are servants of Anubis in the Underworld. They have also taken of Kanderflam in an attempt to learn the forging secrets of the Clan of Dumin. Presumably they are related evolutionarily to surface dwarves. They are mechanically identical to Duergar in 5e.

They worship Anubis and are/used to be (?) his servant in the underworld Duat. Perhaps they were expelled, and their stated fantasy of the "dead rising again" is their belief that they can someday return to the underworld and rule there, undead hordes rising at their command.

They use ghost amethysts to power weapons that exude necrotic energy.