About the only info we know about this faction so far is its name, that it has tie-ins with the Llaelese Resistance, and that they're probably the military arm of The Order of The Golden Crucible, which is a high-tech R&D organisation that was based in Llael before the Khadoran invasion. Since then the organization has taken refuge in Ord. Unlike most other factions' casters whose talents are innate, the Crucible Guard has developed an injectable alchemical serum that can provide warcaster powers to anyone... at a potential cost to their health.
Crucible Guard for Beginners
Faction Aesthetic & Playstyle
Worthwhile first purchases
Renders and Concept art of a crucible guard warcaster named Sylvestro were spoiled at Warmachine Weekend. 
Aurum Legate Lukas di Morray and Aurum Omnus Alyce di Morray are central figures in the Crucible Guard in the Acts of War: Aftershock novel, but have not yet been confirmed as playable warcasters.
It has been confirmed that the Crucible Guard will use warjacks.
PP staff have repeatedly promoted Crucible guard as the first faction with tanks, the top portion of which appear in the Lock and Load spoiler video. There are two weapon loadouts pictured; it is likely to be a multikit. []
Thus far we only know of the Rocketmen. 
Dallas Kemp has been tweeting his painting progress on a medium based robot solo named Prospero.
- Gorman di Wulfe will be available as a crucible guard partisan.
From Acts of War: Aftershock:
Lukas moved to a stand near the back of the armory where a suit of armor hung. Outwardly, it looked like a simple breastplate of yellow enameled steel with pauldrons, vambraces, and greaves. As Magnus got closer, he noticed the network of thin tubing that ran from the breastplate to the other pieces.
Magnus lifted the breastplate from the stand and set it on Lukas’ shoulders. He then noticed the strange contraption that occupied the same space as an arcane turbine on a traditional suit of warcaster armor. It consisted of half a dozen empty tubes, each about six inches long that jutted from the back plate in two rows of three.
Alyce stepped forward to help her husband with the rest of his armor. “There, on that table, you’ll find a case with twelve vials,” she said to Magnus, pointing at a low wooden table covered in ammunition crates.
Magnus found the case she’d indicated. Inside were a dozen vials of clear liquid with attached syringes. They looked like they would fit in the tubes across the back of Lukas’ armor. More of his serum.
Magnus watched as Alyce placed the syringes into the armor, pushing each one in firmly. Lukas grimaced as the needles punctured his flesh.
“They’re in,” she said.
Lukas took a deep breath and turned his right arm over, exposing the underside of the vambrace. A row of three studs or buttons rose from the steel plate, and he pushed the first one. A soft hiss arose from the back of his armor. He sighed like a man who finally had the one thing he most desired. The flesh on his face grew firmer beneath his beard, as if the weeks and months of his captivity had simply not happened. His back straightened, and his chest seemed to gain breadth and power. Aurum Legate Lukas di Morray was beginning to look like the war leader they had risked so much to free.