Hot Coldman first came into the life of Big Boss as one of the planners of Operation Snake Eater. He presumably came up with the idea of taking out the Joy/The Boss-who had “defected” to clear America of wrongdoing.
A decade later, perhaps influenced by the Patriots/CIPHER, Coldman eventually became section chief of a CIA force in Central America, Peace Sentinel-but went somewhat rogue, allying with KGB spy Zadarnov and planning to use his funds and force to build the Peace Walker project-which he planned to use to launch a nuke, just to test the Walker’s use as a deterrent-intending to use as a test, Big Boss’s mother base-something that the fallout of would poison central American crops, which in turn would cause farmers to work as labor building more Peace Walkers. He also took MSF ally Paz-who had alerted Big Boss to this whole situation in the first place (But was, in fact, a Cipher spy) hostage. He believed that the future would be run by smart machines, such as Peace Walker.
However, he was betrayed by his ally Zadarnov, who planned to nuke Cuba using Peace Walker, and frame it on America, thus giving Russia an edge in the Cold War. He shot Coldman. Zadarnov, however, was soon captured himself. As Coldman laid dying however, he managed to activate Peace Walker.
Although Big Boss was still able to stop Peace Walker, it still sent false dummy data to NORAD that strikes were imminent. Big Boss attempted to tell them via phone call, but some members did not believe him (despite him proving his identity to the Chairman). Ultimately though, Peace Walker submerged itself in Lake Nicouraga, causing the dummy data to vanish.
Although research from Coldman’s project would later be incorporated into not only the AI driven Metal Gear Zeke used by MSF( Although Paz made some modifications to pilot it for Cipher), but also the Patriots AIs…making part of his predictions true…
He also has a tatoo on the back of his head, that means “Man is a wolf to man”.
….and just like most of the other Peace Walker characters, he got a Mountain Dew can too.