The humble rotteliver is a Martian insect pest with twelve legs and a hard carapace that makes it notoriously difficult to kill. These like to invade even the most zealously of defended grain stores and supplies, tainting them and making them unfit for consumption. This gives rise to the comparisons, “as tenacious as a rotteliver” or “as resilient as rotteliver.”
Certain species of these insects are omnivorous and will eat carrion or flesh. In fact, some healing shamans use them to treat infections, by setting the rottelivers in the wound and letting them eat the infected and necrotic flesh.
However, this treatment is best performed only by skilled shamans as there are some species of rotteliver that have a taste for living flesh just as well as dead flesh and are not so selective about what they eat. There are reports of entire scouting parties that have been devoured by rottelivers after they had the misfortune of stumbling into a colony.