Time to talk about some very naughty dwarfses.
Ull’vol
The upper, civilized, kingdom of the Duergar. The lower kingdom Ull’vok fell years ago and the Duergar there went mad and became the Derro.
A theocracy ruled by the Hierophant Xadraxim who speaks for the Duergar Creator Diety Molak, the God of Nightmares
Duergar are often cast as slavers and my initial idea was to try something with a whip (think cat rather than Indy) as their symbol and see if the negative space of the fan of tails could represent the peaks rising up above their empire.
Ultimately I felt these ended up too fiddly, the fan either looked too much like a radiant sun (something the gray dwarves are not so keen on) or it was too complex, not strong enough. I still like the idea of a whip, I might return to it as a symbol of their god of nightmares.
My next thought was something using chains or manacles but I want House Argentum to have the fancy knotwork.
Instead I decided to pare it right down, keep it simple, strong and recognisable: bars.
I like the right hand option as a symbol of the Hierophant.
As a motif there’s a lot you can do with it to still leave it recognisable if you wanted to look at variations for houses/orders/castes within Ull’vol. They could be distinctive to all (like the top row), or perhaps only really distinguishable to those in Ull’vol society (lower row):