Plague Drones

Elevation, among plaguebearers, is meant literally. Daemons whose tallies please the Grandfather are raised onto the backs of rot flies and sent aloft as Plague Drones, surveying the advance of contagion from on high and correcting any regrettable outbreaks of health. From their saddles they hurl death's heads into massed ranks and mark the Tally's progress across whole warzones at a glance.

Rider and mount are a study in contrast. The plaguebearer above surveys its work with gloomy satisfaction; the rot fly beneath hates everything that draws breath and bites with a spite all its own. Armies that stand firm against the legions' trudging advance often break at the sound overhead instead: a drone that swells until the sky itself seems infested, because it is.