Epidemius, known also as the Maggot King, the Plagued Panjandrum and Reckoner of Mortality, is Nurgle’s chosen Tallyman, one of the seven Proctors of Pestilence and the cataloguer of all the Plaguelord's diseases.
Epidemius' task is an unending one, and it generates a great deal of paperwork, so he rides a palanquin to share the burden — and to more easily force a path through Nurgle's hordes. Two dozen Nurglings attend the Tallyman's every need, providing the parchment, operating the death’s head abacus, excreting the ink for the quill pens and even defending Epidemius from harm should a foolish enemy venture too close.[1a]
Epidemius brooks no idleness or distraction from his helpers who, unlike other Nurglings, remain deathly silent lest they disturb their master from his task and thus rouse his ire. Like Nurgle, Epidemius abhors anything that distracts from the serious matters of life and death. The only sounds that can be heard are the gooey shufflings as Nurglings heave the palanquin forwards, and the irritable scratching of the Tallyman's quill as he seeks to keep his records up to date. From his perch, Epidemius surveys the thrift and splendour of Nurgle's creations, making note of casualties and infection rates as well as secondary symptoms such as unusual colourations and odours. This information, properly collated and distilled, is of incredible value to Father Nurgle, but must be recorded with absolute precision and in a timely fashion to be of any use.[1a]
Epidemius' path through the mortal and eternal realms is an unpredictable one, for he goes wherever the spoor of pestilence leads him. He is busiest of all when Nurgle's power is strong, for the might of the Plaguelord is inextricably linked to the constantly shifting ebb and flow of disease. Campaigning armies, with all the poor hygiene and unmentionable diseases that entail, offer a glut of work for the Tallyman, but also present rare opportunities for more unusual studies.[1a]
Of greatest interest to Epidemius are infections and fevered behaviours afflicting determined or ambitious souls. Nurgle's cankerous plagues do not merely infest the physical form, they also run virulently rampant throughout a being's soul, destroying his sense of self and moral direction as thoroughly as they corrupt his fevered body. Observing this decline is a rare privilege. A skilled observer - and there are none more skilled than the vile Epidemius — can read this flaked and crumbled trail of soul-stuff as it departs the mortal coil, gleaning all manner of knowledge and adding a portion of the spirit’s strength to his. As an offer of thanks, Epidemius' entourage strike bells and gongs when such a soul finally succumbs, ushering the tainted spirit into Nurgle's paternal and welcoming embrace. What happens to it there, none can say — least of all Epidemius, whose interest in a subject dies along with its physical shell. Happily, there are always fresh victims to investigate...[1a]