Forge of the Chaos Dwarfs is without a doubt the best Total War: Warhammer expansion ever made in terms of hats. Whether it's the little red pointy cowls of the hobgoblins waving from side-to-side as they scurry in for a stab, or Astragoth Ironhand's literal stovepipe putting Brunel to shame as he sprints into combat atop the deadliest mobility frame ever conceived.
That's all the chaos dwarfs are really; take the crotchety old man vibes of the regular dawi and combine them with a love for slave-mongering and arms manufacture—the aged grandparent you remember, but more liable to burn you alive or send you to the mines than dole out a stern reprimand.
If regular Warhammer dwarfs are old men, the Dawi-Zharr are slightly younger old men, less inhibited by silly ideas like 'traditions' and 'morals' and why you probably shouldn't combine volcanoes and guns—there is no reason, they're the best. The chaos dwarf artillery pieces and war machines put their western cousins to shame; there's nothing as simple as a cannon here. Instead, they have the napalm of Deathshrieker Rockets arcing down on enemies from above, trains with machine guns bolted to the front, and best of all, the Dreadquake Mortar.
I don't think I've ever seen an infantry unit completely wiped from existence in a single volley before; I'm not talking down to minimal health with a few models running away, either. There was a unit of Dwarf Warriors a second ago, and now there's just the aftershock of the mortar shell. War engines also come equipped with the More Power! ability—effectively a choo choo button—that puts the engine into overdrive, increasing mass and speed to mow down any enemy silly enough to approach.
The chaos dwarf campaign is all about finding and corrupting dwarf relics to feed into a super drill so the Dawi-Zharr can break into the realm of their daemonic bull god: Hashut, Father of Darkness.
Such murderous innovations are costly, though. The typical chaos dwarf campaign experience boils down to establishing an infrastructure that allows you to support your chosen flavour of death, be it trains, artillery pieces, daemonic K'daai, or a gunline of blunderbusses. Each unit comes with a cap that can be expanded at the cost of armaments in the Hell-Forge, and this also unlocks upgrades to that unit in the Manufactory. Chaos dwarf units are already some of the most powerful I've seen, but you can make them even better in campaign if you're willing to pay armament upkeep.
The chaos dwarf economy is undoubtedly the most complex CA has ever created in Total War: Warhammer. More RTS-centric players might find it a little stifling at first—I know I did—since expansion is no longer a simple process. When you take a new settlement, you now need to decide whether it's going to be a factory or an outpost. For the former, you've got to consider whether you have the required raw materials to produce armaments, and for the latter, the necessary workforce to staff a mine producing said materials, though you can change your settlement type after the fact.
The early campaign is a constant book-balancing affair as you fight lots of battles to acquire more labour, and shift it around your provinces to make sure your mines are operating at full efficiency. You can also send military convoys out into the world to trade your armaments and cash for materials, money, or even more workforce. This is partly why I chose Zhatan the Black since he gets an extra one, though I do also like his cute beard skulls. For me, it was a begrudging optimization at first, that blossomed into complete obsession when I realised how quickly the chaos dwarfs can grow. Resources like marble, timber, iron, and obsidian help you create super provinces with absurd production output, plus it's satisfying to see a constant stream of trains chugging away from Zharr-Naggrund to sell your homemade guns.
While a bit of a chore at first, the chaos dwarf economy is addictive as hell when things slot into place. You acquire labour to mine raw materials, you turn raw materials into guns, you sell guns for more labour, so you can expand and open more mines. Any surplus workers can be sacrificed to Zharr-Naggrund for Conclave Influence, a resource used to claim seats in the Tower of Zharr for buffs and abilities, while climbing the greasy ladder of the Dawi-Zharr hegemony.
I went full-on cookie clicker at first, forgetting that there was even another use for armaments beyond packing them into convoys so I could purchase ever more workers, but provided you keep acquiring labour, you can expand your overall production capacity very fast. By turn 60 I had 20,000 armaments, far more than I could ever sell. Like a chaos dwarf warmonger staring at his big pile of weapons, wondering if there's more to life, I realised I had to use my ill-gotten guns to enjoy myself, so I splurged on artillery unit cap and forged eight Dreadquake Mortars.
This campaign and battle balance is what makes Forge of the Chaos Dwarfs such a great expansion. Whether it's upping your armament production so you can purchase additional units or upgrades, or claiming seats in the Tower of Zharr for powerful army abilities, it feels like you're building a personalised infrastructure that'll let you be OP in battles in a way that's enjoyable for you, and I think that's the best kind of economy that can exist in Total War.
For me, it was all hobgoblins and artillery, since the hob mercenaries become downright broken when you get access to their hero, Gorduz Backstabber. Chaos dwarfs are definitely one of the strongest factions in the campaign, especially as their race capital of Zharr-Naggrund is every bit the Mordor-esque hell fortress you'd imagine. I wouldn't be surprised to see them dominate Immortal Empires, but OP races can be very fun, and I think successfully realising a faction with a more complex economy like this is going to make for some great future expansions.