Gammorin was one of the leaders of a super mutant faction that fled to the east after the death of the Master and the destruction of the Mariposa Military Base. Sometime after their departure, Gammorin's mutants were pursued by Brotherhood of Steel airships. While most of them ended up in the vicinity of Chicago, far from Gammorin's forces, one of the zeppelins crashed north of the mutant encampment. The leader, Paladin Latham, challenged Gammorin to a single unarmed combat and, to surprise of everyone, killed the mighty mutant.