Warp-Grinders are a smaller and more portable version of a much larger drilling machine first devised by Clan Skyre as a means to tunnel far more quickly than a horde of slaves could ever hope to achieve.
Some of these massive constructs are larger than the grandest ships of the Empire's navy. These huge devices combine great drills with warp energies to vaporise the broken debris as the machine bores. These rare machines are seldom, if ever, seen, but a portable version can be often found on the battlefield.[1a]
The more portable War-Grinder opens up tunnels. Projectors gleam with warp-energy, pulverising stone and leaving a narrow and smoking passageway in its wake. Small fast-moving units can follow the device, emerging behind enemy lines to cause untold disruption. But it is a perilous trip, as the newly-bored tunnels are prone to cave-ins and the machines can suffer catastrophic meltdowns. When the Warp-grinder breaks through the surface, it will stick with the unit it is attached to, even assisting in close combat. Without the comforting presence of the parent unit, the Weapon Team will flee the battlefield.[1a]