Martin McCullister (Game Of Shadows)

Martin McCullister is an accomplice of Sebastian and a high ranking CIA member, that has always been the insider for Sebastian regarding CIA operations and intel, Sebastian used against the Patriots. However this changed when Sebastian discarded him, due to Martin failing to get more intel about the new unit Eishr, that was responsible for wiping out several soldiers of Sebastian. 
After been discarded, he again attempted to get Sebastians attention, by planting a bomb in the server room of the CIA, deleting every single information about Sebastians, Alices and ironically John and Dahlias identity making them what John calls; Phantoms. 
After bombing the server room, he begun to work with Sebastian again, only to be noticed by Michael who in turn contacted John and managed to trace Sebastians whereabouts by following Johns instructions. However Michael was then heavily wounded by a bomb set off by Martin. He later died due to his injuries, making John lose his sanity for a while. 
Martin attempted to flee, only to be confronted by an enraged and temporarily insane John who shot off his right leg and shot him in the back several times. To increase Martins pain, John shot him in a way, that the latter would survive the gun wounds for the next hours. 
With that Martin was left crippled and bleeding out to die in the desert.