Mutants are mean and have a beef to pick with the world. Cross their path and they'll hold a grudge with you. It is hard to tell what will enrage a mutant. Mafia members have often seen mutants walking through the city streets suddenly charge a building and leave nothing but its ruins behind. That said, moving things tend to draw a mutant's attention more easily than a statue would. Beware of your encounter with a mutant, if you get too close, they will stalk you down.
They will often drop Painkillers.