The Kill Master is a shamanistic bass guitarist who lives at the peak of Top Hat Mountain and whose second passion in life is riding his tricycle motorbike. The Kill Master is voiced by and modelled on Ian "Lemmy" Kilmister, front man of the famous metal band Motörhead. In the Brütal Legend universe bassists have the power to heal the wounded and the Kill Master is particularly skilled at this. When Ophelia is wounded Eddie Riggs takes her to the Kill Master so that he may heal her, however even his powers remain ineffective and he informs Eddie that he must retrieve strings from the lair of the Metal Queen for his bass if he is to be able to heal Ophelia.
He joins Ironheade to help them pursue General Lionwhyte and takes on an identical role in battle to Ironheade's Thunderhog units. Later in the game he is able to gain the trust of Rima for Ironheade by healing her and her metal beast. In stage battles, the player can double team with him, riding on top of his bike and performing stun notes.