The Steam Tank is one of the rarest and most feared war engines ever fielded by the Empire of Man, a massive armoured hull of iron and brass driven forward by a roaring pressure-boiler. Only a handful survive from the golden age of the engineer Leonardo of Miragliano, and the secret of their construction has long since been lost, making each surviving machine a priceless relic of a bygone era of genius.
Each Steam Tank must be coaxed to life by a dedicated engineer-commander of the Imperial Gunnery School at Nuln, who must nurse the temperamental boiler lest it burst and immolate its crew. Trailing plumes of black smoke, the tank grinds enemy formations beneath its wheels while its steam cannon shatters walls and monsters alike.
Because so few remain, an Emperor commits a Steam Tank to battle only at moments of dire need, and its appearance alone can rout lesser foes who have never faced so terrible a contraption of the age of reason.