Here is a blurb I wrote about him and his Stormhost:
Hanzbur Anvilhelm leads the first Warrior Chamber of the Forgesworn Eternals, known colloquially as the Anvilhelms.
Grungni was commissioned by Sigmar to reforge the many heroes allover the realms. They were to become the Stormcast Eternals, Sigmar's greatest weapon against Chaos. Grungni asked for one stormhost he could reforge himself for his own. Grungni knew of the plight of the duardin and worked on creating what would become their greatest ally in their battle against Chaos. The heroes of the realms for this project couldn't be just anyone. Outlying some of the duardin holds were human settlements of hardy individuals who shared a close relationship with their duardin neighbors. They were tough and grim folk with the same respect for keeping promises and paying debts. One individual among them was a brave warrior named Hanzbur who fought alongside many duardin defenders against chaos incursions. Grungni took note of this one because he saw the duardin as equals to his own kind, and not inferior.
Hanzbur was taken up into Azyr during a particularly brutal campaign. Grungni saw to his reforging personally. Crafting for him his finest weapons and armour. This new Hanzbur Anvilhelm would need a suitable mount. Since the dracoths were given to Sigmar, Grungni had to find another animal companion for his Lord-celestant. Among the silver mountains on Chamon are a breed of tough ursine creatures, with light grey fur and ferocious demeanor. These creatures were part of legend for the humans and duardin of the area, and known to be untameable. Grungni could think of no better mount, and first cast Hanzbur to a remote secluded area of the mountain range to find and tame one. This was no easy task and took several months. With Hanzbur reforged, the dire bear could sense a commanding respect within him. Hanzbur then forged the bear's harness and armour himself. He called his companion Storbjorn, after the language of his past life.
With this union complete, the rest of the Anvilhelms were cast to Chamon. The Forgesworn Eternals had been brought finally in full. As the liberators, retributors, and the rest of the host looked up from their landing, they beheld the inspiring sight of Hanzbur atop his bellowing Storbjorn. They would soon join with Sigmar's other stormhosts on the realm, and the liberation of Chamon would begin.
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