It is a mistake to think that all Dwarves act alike. Sure, most of the Dwarves you meet will love to mine, have a fondness for gold and would happily spend entire lifetimes digging, finding secret doors and collecting gold. That is because the other kind of Dwarves don’t hang out in bars and mines. They are too busy making really weird shit.
They call themselves the Followers of the Twisted Gear. These Dwarves have left their homes in search of something more intellectual than digging and mining. Many times their numbers include adolescent Dwarves who are rebelling against the old ways. They have shave their beards in an act of defiance for the old ways and instead let their hair grow to ridiculous heights; often using the blood of others for their hair gel. They pierce their skin with gears and tools. The Followers of the Twisted Gear is a refuge for Dwarves of a Chaotic alignment.
And what do these Twisted Gear Dwarves do? They invent. They seek out dark places of wicked evil to absorb inspiration. They lurk in infamous tombs. They have long drinking parties in cursed cemeteries. They squat in abandoned hideouts of long dead villains. Anywhere that evil once reigned; the Followers of the Twisted Gear will take residence for inspiration.
In time, one Dwarf will get an inspiration. He will develop a mania to build a great device. The device is almost always made from the remains of living creatures and these devices are often mistaken as tools of necromancers. Sometimes living creatures are trapped in the devices as if their very suffering is part of the mechanism. These manic Dwarves will incorporate magic and technology in strange hybrid manners that
The purpose of the device vary from creation to creation. They rarely create something practical as that is too much like the normal Dwarves that they scorn. No, the Followers of the Twisted Gear might make a mirror that shows you random events across time and space. They might make a ship that travels through underwater but it never stops traveling; condemning the passengers to eternal wondering. Or they might make a pair of pointy shoes that bestows any effect on the potion table every time you put them on.
Dwarves of the Twisted Gear will have the same stats and organization of normal Dwarves in your campaign. Despite their desire to be different, some habits are just hard to break. Each lair of the Followers will have D3 random devices that are each unique in the world.