Fungal Zombie Infection

Spores from the Letum Comet will settle in strange places within the Kilmara system. Sometimes found in the depths of space, other times raining down on planets below. Since the comet has been trailing these spores for almost a thousand years there is always a chance the comet may be far away and a cluster of spores falls on a planet with no warning.
  The spores transform dying plants and animals into a fungal zombie. While the zombie retains some features of it's original features, they seek to generate new zombies by killing animals. While originally spores can infect dying plant matter, the zombies seem to have a preference to kill animals, monsters, and people. This is theorized this is because many large plants decay slower and smaller plants are less nutritious for the fungi.
  Trees dead for many years to where they are soft and crumbing become a good source of fungal zombies, in addition to dead Orac's and other beasts. This transformation can be devastating if it falls on cemeteries and reanimates the dead of local populations. This fueled better forms of Consecration to prevent infestation and random fungal zombie growth.