The Abyssal Dwarfs are twisted and evil parodies of their nobler counterparts. Blacksouls form the backbone of the army, marching in large infantry blocks whilst the black powder wielding Decimators fire into opposing ranks. They use slaves to bolster their numbers and construct dark war machines to rain fire and destruction upon their enemies.
The last time the Abyssal Dwarfs marched in unison, it was under the command of the Overking himself, aided by the legions of the now dead Supreme Iron-caster, Arhak Soulbinder. Arhak had discovered the location of the lost dwarf hold of Hirath Dur, reputed to be the location of the fabled Quartz Sceptre, capable of subduing even the most resolute will, making its bearer capable of ruling the world. The War of the Quartz Sceptre brought Zerkziz and Arhak into conflict with the Free Dwarfs, led by the Berserker Lord Sveri Egilax, king of Cwl Gen. A bitter campaign that almost saw the Free Dwarfs wiped from the face of Pannithor.
– lore snippet from 3rd Ed. Rulebook