Sergeant James Buchanan "Bucky" Barnes is the childhood and life-long best friend of Steve Rogers and a member of an elite special unit of Allied soldiers formed in World War II known as the Howling Commandos. He was assumed deceased after falling off of Zola's Train. Unbeknownst to the Commandos, Zola's experimentation allowed Bucky to survive the fall. HYDRA subjected him to brainwashing as part of their "Winter Soldier" program. Under HYDRA's control, Bucky would be responsible for countless assassinations including political targets. Bucky became a formidable fighter and an even more ruthless killer. His experiences with the KGB would earn him the name of the Winter Soldier.

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