The Rampager squads of the World Eaters were formed of the most savage and bloodthirsty Space Marines in a Legion already notorious for its fury in battle. All underwent the prohibited psycho-surgery that Angron is believed to have instigated among his favoured sons, and those who survived honed their newly enhanced desire for berserk slaughter through martial discipline and the mastery of cruel and vicious weapons adapted from the arena combats in which the Red Angel fought during his youth.