While the Mauler is weaker than the human shotgun because it cannot perform instant kills, there is a way to achieve an almost instant kill. To this you must be in melee distance of the target. When your Mauler's target goes red fire one shot. Follw this up with an immediate melee. This kills the opponent instantly and if you master the skill you will be able to do this before the target has time to shoot you ... There is a glitch that lets the wielder, with appropriate timing, to melee attack and shoot the Mauler at the same time, generally causing instant death. This unfair advantage has lead to it being labeled a "noob" weapon.