The Bronze Vipers were an 8th Founding loyalist Space Marine chapter. They were tasked to patrol the boarders of Zoragon space, although they also fought Eldar forces as well. As a result they established tactics revolved around Xenos hunting. In M39.204 Eldar craftworld Nirmia destroyed most of the chapter. As the chapter was trying to recover the Zoragons launched an attack annihilating the rest of the chapter.