The Biomen were the result of the Bioman project. Commissioned in the year 2000 Von Bach Industries was responsible for much, if not all, of the work done to create them. It took almost 20 years for scientists to perfect the biomen. Human rights groups argued over the moral dilemmas of creating sentient beings. After the end of the Pale Wars Biomen became obsolete and the Earth Republic tried to integrate them into security forces, but their aggressive nature caused problems causing them to become stigmatized by both Humans and Votans. Some of the biomen in the Bay Area became Mutants.
They always carry around big guns, they can do a lot of damage if they get you from the behind.
There's nothing really special about them, except for the fucked up mouth... they probably have something evil hidden in there...