The title of this article is conjectural. The subject has no canonical name.
Marine 4L was a DMC soldier who served as part of Ghost Program propaganda. In a film, he took part in a battle against alien forces, successfully defeating some zerg only to be pinned down by protoss dragoons. A ghost saved him by destroying the dragoons with rocket propelled grenades and subsequently calling in a nuclear strike. 4L thanked his savior, calling ghosts "lifesavers."