A former officer of the 107th Infantry Regiment, and Steve Rogers’ best friend since their childhood, Sargent James Buchanan “Bucky” Barnes fought as Captain America’s partner and ally in World War II against HYDRA forces. Captured, he was used as a test subject, receiving a variant of the Super-Soldier Serum created by scientist Arnim Zola. Rescued by Rogers, he and Captain America created the group Howling Commandos, an elite combat unit to face Red Skull’s forces. Ambushed in the Austrian Alps, Bucky fell hundreds of feet from a train and was considered dead. However, his skills enhanced by Zola’s serum enabled him to survive, even with the loss of his left arm. Captured by Hydra forces in the Soviet Union, he was brainwashed and armed with a new cybernetic arm, known as agent Winter Soldier. For 50 years, he was used as an assassin by Hydra, being put in cryogenic stasis after each mission to guarantee his longevity. When he received the task to eliminate Nick Fury, he ended up being challenged by his old friend Steve Rogers, who little by little helped him remember his past life.