Karalgin Tharuk
A master Daemonsmith-Alchemist, Karalgin was a bit of an anomaly in his early carrer. His magical powers were middling by the standards of Zharr-Naggrund, but he had a talent for machinery and an even greater passion for alchemy. For a long time he was content to ply his trade, experimanting with variety of infernal concoctions and slowly climbing the social ladder, until his 76th year of life. Most probably supported by his competitors, Karalgin's Hobgoblis subordinates organized a resistance. When he moved to deal with them, a sabotage in machinery directly exposed him to acrid and poisonous gases borne from his work. He survived, albeit with acid-burns on his face, horrifically damaged lungs and severely thinned beared, becoming a subject of mockery - what self-respecting Dawi-Zharr would let himself get so wounded by mere slaves?
As if to spite his detractors, Karalgin became only more passionate and determined in the aftermath. He used his engineering skills to craft for himself a device to help him breathe - Brazen Beard, as he called it, was a metallic face-mask connected with an alchemical apparatus constantly concocting a healing vapour-mixture, carried on one's breastplate. The design surprised the Conclave of Sorcerers and many daemonsmiths bought a later, mass-produced version, considerably improving Karalgin's finances. Established once again, he threw himself into work, producing and inventing a great many alchemicals, his crowning achievement being a contract for supply of alchemical weapons to Infernal Guard. While he seems to lack political ambitions, he is one of the favourites for the Seat of Black Alchemist during the next shuffle in the Tower of Zharr.
Alchemicals:
Blood Fire
Invented by the Sorcerer-Priests from Gorgoth and perfected by Karalgin Tharuk, this substance has a rather unassuming look: a simple white powder. Despite that, it's a dangerous alchemical, capable of self-ignition even without particularly harch treatment, and when combined with alchemical oils, it easily sticks to skin. Even in raw form, it can explode violently, with burning chunks capable of searing deep holes in the unprotected flesh. Created by alchemical refinment of apatite and similar ores under high temperature.
Wilting Oil
Invented by Karalgin Tharuk on the orders of Zhathan the Black, Wilting Oil is the precursor for many terrain-denial chemical weapons used by Dawi-Zharr. Produced by mixing highly alkalic salts, liquid bitumen and daemonic elixirs, this substance is a thick, black oil with immense corruptive and pollutive properties, capable of defoliating a plant in seconds and turning grasslands into desert in few days. While it resembles rock oil, it's not flammable, but its effects on the environment are similar - a barrel of Wilting Oil poured into the ground can befoul a village's worth of terrain and render it incapable of supporting plant life for decades. It is forbidden to use it within Darklands, to preserve what little farmland there is, but a large stock is kept in Zharr-Naggrund (to ensure compliance of Dawi-Zharr lords) and in border garrisons, particularly those close to south-east, for the campaigns agains Dragon Isles' Lizardmen and in case the rumours about Wood Elves in jungles of the east were true.
Black Smoke
The greatest creation of Karalgin Tharuk, Black Smoke is an alchemical weapon of terrifying potency. Its recipe is closely-guarded secret, but rumour has it that among the ingredients are various forms of alchemical waste, refined rock oil and sacrificial blood. Resembling black water, under normal conditions this substance quickly evaporates into thick, black vapour. Almost odourless, the Black Smoke is nevertheless extremely choking, irritates the throat and lungs when inhaled and is extremely lethal, as even skin exposure is enough to kill in a few hours and afflicted bodies have been reported to outright melt. Infernal Smokers, sub-division of Infernal Guard tasked with using Black Smoke on the battlefield, are most respected and most reviled soldiers in its structures - due to Smoke's high lethality, a single armour leak generally leads to death, which lead to "recommendation for service in Black Smoke Division" becoming the closest thing Dawi-Zharr have to death penalty, reserved only for worst of the worst; on the other hand, members of Infernal Guard who volunteer to that branch earn admiration on par with those who join The Immortals. Service in Black Smoke Division is generally shortest of all Infernal Guard divisions - either due to quick death or quick pardon.