Frank Horrigan it the ultimate foot soldier for the Enclave–though ‘walking tank’ might be a better description. Starting as an unstable soldier deployed in the ruins of California, he quickly became known as a brutal instrument of murderous efficiency. While on a mission to the Mariposa Military Base he was exposed to FEV, beginning his mutation. He was experimented on still further by Enclave scientists to exacerbate his aggression, size, and strength, to the point where he could decapitate a deathclaw with one blow and put his first through the combat-armored chest of a Brotherhood of Steel knight.  Horrigan’s size and strength are not coupled with strong will or sense of self. Repeated conditioning made him utterly loyal to the Enclave and its president, willing to deal out casual violence with no thought and return to his masters for the next mission. His limited conversation and rigid loyalty to the cause make him a fearsome adversary; few stand against him and live to tell the tale.