Rolling Death is the translation of a Stofonian phrase that refers to powered, armored, military assault vehicles of every kind. The term encompasses both vehicles that we would recognize as "tanks", as well as lighter vehicles with rubber tires.
The term "Rolling Death" generally only applies to vehicles actually intended to be driven in combat. Vehicles used as transports for troops or supplies are called by other names, as are vehicles with guns so large that they cannot be fired without first anchoring to the ground.
Rolling Death machines first appeared in the Last War. These earliest examples had metal wheels and were powered by steam. They were slow, bulky, and generally ineffective, but they left a lasting impression due to sheer novelty.
Between the Last War and the Fracture, the internal combustion engine replaced steam, and metal wheels gave way to rubber tires on the lighter models and tracks on the heavier models.
The light, fast versions were frequently used between the wars in anti-insurgency campaigns in Juturia.
Rolling Death of all type were heavily used in the early days of the Fracture, but by the later days of it fuel supplies had become too exhausted to keep the machines running.