Motörhead's overwhelmingly loud and fast style of heavy metal was one of the most groundbreaking sounds the genre had to offer in the late '70s. Though the group's leader, Lemmy Kilmister, had his roots in the hard-rocking space rock band Hawkwind, Motörhead didn't bother with his old group's progressive tendencies, choosing to amplify the heavy biker-rock elements of Hawkwind with the speed of punk rock. Motörhead wasn't punk rock, but they were the first metal band to harness that energy and in the process, they created speed metal and thrash metal.