Rhuaxan Dwarf

Rhuaxan dwarves, also known as 'volcano dwarves,' are a race of dwarves that built civilizations around the molten rock of active volcanoes. They worked with obsidian to craft weapons and armor and used magma to build their homes.
In ages long past, they were known as the primary dragon slayers in the world. Their mysteriously forged obsidian armor protected them from dragon fire. Rhuaxan dwarves are seemingly gone from the modern age. Many of the relics of their culture still exist, as do the ruined remains of their civilizations, but no volcano dwarves are known to be alive.