For decades before Thunderhead’s construction, Nemo had considered the possibility of a warjack fueled by electricity, able to function without coal or water. The advantages were obvious—not only might such a machine run more efficiently than one operating under steam power, but would also be considerably quieter and more stealthy on the battlefield.

Achieving this feat, however, proved difficult. At the heart of the problem was creating an electrical generator powerful enough to operate a warjack. Smaller devices already existed in various instruments and even weaponry, but scaling them up resulted in dangerous and unstable engines. Several early prototypes failed in spectacular explosions, destroying thousands of crowns’ worth of equipment and badly burning Nemo’s assistants. Later attempts to add more shielding and a larger housing were counterproductive. The revisions increased safety, but in doing so, dramatically increased the weight of the warjack and significantly reduced operational efficiency.

His enthusiasm undiminished and sure that his ambitions could be achieved, Nemo continued with the project. Having reached the limits of conventional Cygnaran engineering, he began investigating other leads, which eventually led to contact with the Cyrissist cults that worshipped the Maiden of Gears. Realizing their technology held the answers he needed, Nemo undertook a sabbatical and spent months working alongside these individuals, attempting to glean as much information as he could.

Nemo eventually had a proof-of-concept that could generate sufficient power without risking overloading, and would be small enough to fit into a heavy warjack chassis. In 604 AR, he finalized a series of blueprints for the machine and named the project Thunderhead.

Thunderhead is the original storm made manifest; the galvanic blueprint that shaped every warjack that came after. Torn apart, studied, and rebuilt in the wake of war, Thunderhead returns not as a relic but as a reminder that the storm never left; it was charging up. This isn’t just any warjack off the assembly line. It’s a super heavy achievement that represents the height of Cygnaran technology — for now.

Thunderhead, Heart of the Storm’s Heroes & Villains lore is now in the Warmachine app for subscribers. Got thoughts? Share them on Discord..

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