Mutant Power-suit Survivors

In a post apocalyptic world what remains of Humanity survives in bunkers to protect themselves from the mutant monsters outside. Whenever they go outside whether it's to get food or for repairs on the bunkers entrance they use power suits to help them defend themselves from the mutant animals. However the suits abilities have a drawback and that is they'll drain their wearers energy if they use it. However theirs someone out there who's suit has all the current abilities that the individual power suits have and they don't get drained at all. They also have other forms of technology to kill the mutants, could they be the key in humanity's survival.