His mask has an integrated electrolaryns, indicating some vocal chord damage; possibly related to his facial disfigurement. Not clear what caused this damage, but it looks severe. No known military record, but he's far too proficient a hit-man to be self-taught. His past targets include high-ranking cartel members, so it's doubtful that he's involved with that crowd, either.
Scourge: Outbreak pits the veteran mercenaries of Echo Squad, against their sworn enemies, the Nogari Corporation, in a desperate mission to rescue a double agent hidden behind enemy lines and to recover a mysterious meteorite fragment from Nogari's possession. Convinced that Nogari's 'Ambrosia Fuel Technology' is connected with deadly plagues that threaten to ravage the world, this may be Echo Squad's last and only shot at bringing the Nogari threat to its knees once and for all.