It is learned near the end of the eighth season that Knowle Rohrer is a super soldier like Billy Miles. Although super soldiers are strong and indestructable against usual weapons, they can be killed with a certain metal alloy. Knowle dies in a New Mexico desert while chasing Doggett and Monica Reyes. The metal, which was in the rocks behind Doggett and Reyes, turns Knowle's body into a mass of metal and he then flies and slams into the rocks.