Lawrence Barrett

Barrett appears to be one of the game's antagonist in Deus Ex: Human Revolution.

Biography
It's the leader of the mercenaries of the private military company Bell Tower in Heng Sha. It has a gatling gun-type concealed in his left arm and he is heavily mechanical-augmented.

Behind the scenes

 * His name appears to be a reference to Square's Final Fantasy VII, where one of the playable characters is named Barret Wallace and has a prosthetic arm in the form of a gun.