Doomwheel

The Doomwheel is one of Clan Skryre's signature lunacies: a colossal rolling wheel of iron-shod timber, spiked and caged, with a Warlock-Engineer strapped into its hub amid a nest of crackling warp-generators. Driven forward by a captive scurrying mechanism and its own gathering momentum, it careers across the battlefield grinding everything beneath it to paste, while the engineer hurls bolts of warp-lightning at anything the wheel has not already flattened.

The trouble is that a Doomwheel is only nominally under control. It lurches wherever its unstable engines and the terror of its pilot send it, as dangerous to the Skaven ranks behind as to the enemy ahead, and the warp-lightning that is its glory arcs out in directions no one intended. Yet when it works (when it rolls true into the massed enemy, spitting green fire and crushing all before it), few war machines in the world can match the carnage. Skryre engineers judge the risk entirely acceptable, chiefly because it is someone else's.