Virtually nothing is known of the past of the man known only as Berzerker before he joined the underground community of mutants known as the Morlocks who lived in "The Alley", a huge tunnel located beneath Manhattan. Berzerker came to lead an offshoot of the Morlock community known as the "Tunnelers", who despised the other Morlocks, whom they called "Drain Dwellers".
Seeking to escape the massacre of the Morlock community by the superhuman team of assassins known as the Marauders, the Tunnelers escaped to the surface world. After an encounter with the notorious Savage Wolf street gang on one of the Hudson River's dilapidated piers which subsequently led to a clash with the New York Police Department,Berzerker was knocked into the river by an optic blast from Cyclops, then-leader of the superhuman team of mutants known as X-Factor. As Berzerker hit the water, the electro-magnetic energy stored within his body was explosively torn from him.
Recently, Berzerker was revived with an alien techno organic virus.