Daemons

All the special rules for daemons apply as described in the Warhammer rulebook. In particular note that the Plaguebearer has a saving throw of 4+ due to its daemonic intangibility or daemonic aura.

Plaguesword

The Plaguesword drips with venomous slime. A wound from this weapon will kill mortal creatures on the D6 roll of a 4 or more, regardless of how many wounds the target can normally sustain. Note that this only applies to mortal creatures - not daemons or Undead.

Fear

As daemonic monsters the Plaguebearers cause fear, as described in the Psychology rules.

Cloud of Flies

Plaguebearers are surrounded by a black cloud of flies. When the Plaguebearers are fighting these evil buzzing creatures fly into the eyes and mouths of their enemies, clogging their ears, and crawling up their nostrils. This is a terrible distraction, so any enemy fighting a Plaguebearer must deduct -1 from all his to hit dice rolls.