Institute super mutants are the variant of super mutant found throughout the Commonwealth, Nuka-World and the Island in 2287. These mutants were created by the Institute by means of exposure to the Forced Evolutionary Virus (FEV). They are massive, muscle-bound creatures with an innate immunity to radiation and disease. They are most frequently encountered in central Boston, and can also be found in Fallon's department store, Fort Strong, Trinity Tower, Revere satellite array, Big John's salvage, Gwinnett restaurant, and several other locations all throughout the Commonwealth - most of which can be identified by the telltale signs of hanging meat bags, twisted girders protruding out of the ground, cages, and gory waste piles that they enjoy decorating their surroundings with.