Powers: Size based
Fred Dukes began to use his mutant powers in a freak show, where his oversized body and mass attracted many visitors. His life would stay like this if not for Magneto. When the master of magnetism was forming the first Brotherhood of Evil Mutants, he went for Dukes. Then he learned how to use his powers in evil ways, controlling his density to make himself immovable and to trap others inside his fat. He, along with the other members of the Brotherhood, became one of the X-Men worse enemies, fighting many times against them.
After Magneto left the leadership of the Brotherhood, Mystique became their leader. Their first mission was to kill Senator Kelly, but he and the other were stopped by the New X-Men. The Blob was arrested, but set free some time after by Mystique and Rogue. Some months later, when the government offered the Brotherhood to become the Freedom Force, Blob turned into a worker of the government, but not for a long time.