MUTANT MONSTERS

Game masters can create memorable encounters by adding a minor mutant, major mutant, or true mutant template to an existing NPC or creature. For the GMs convenience, each of the mutant types are also presented as grafts for use with the creature and NPC creation mechanic.

Mutants will allow you to reuse some encounters.  As the GM you know it’s the same encounter your players faced in a previous gaming session, but the players won’t.  Mutations are a convenient way of recycling old encounters while giving them a completely new feel.  Remember as a GM you can essentially do whatever you want to create your story.  If you are pressed for time and the “True Mutant” template seems like too much work then take a common creature from any source and throw a mutation or two on it.  Just remember to increase the CR for the encounter by 1 or 2 for creatures with Tier 3 or higher mutations if they don’t have compensating deformities.