No Resistance to Bacteria (or Bacterial Susceptibility is 2nd edition): The mutant with this defect will have little or no resistance to sickness, making any infection or illness a serious thing. It is necessary to have disease-causing agents in the game if this mutation is used. A cut from a dirty sword may cause blood poisoning. The scratch of the claws of certain meat-eating creatures may cause serious infection, or a simple cold, caught from a tribesman, may turn into pneumonia. All of these examples may cause up to 10 points of damage per day, and are very hard to cure.

No Resistance to Poison: Exposure to any poison will kill this mutant unless the appropriate antidote is quickly administered.