Tasmanian Face Eating Zombies

Mean Tasmanian devils get cancer; nice ones don’t 

The devils have been afflicted by a terrible plague — an infectious cancer, only one of two in the world, that guarantees that its victims will die a horrible death. The cancer causes tumors to grow all over the devils’ faces, which keeps the victims from eating, and they eventually starve to death.
But the cancer doesn’t attack all devils equally. It is the most vengeful devils, the most aggressive, the most likely to bite other devils’ be-tumored faces that are most likely to contract the disease.