James Barnes

Sergeant James Buchanan "Bucky" Barnes, is a World War II veteran, a former officer of the 107th Infantry Regiment and best friend of Steve Rogers since childhood. Barnes enlisted in the army and assigned into the 107th in 1943. His regiment was captured by HYDRA, where Barnes was experimented on by Arnim Zola. Barnes, along with whoever still remained from his regiment, were later rescued by Rogers, who had become Captain America during Barnes' absence. Upon joining forces in the continuing war, Barnes and Rogers formed the Howling Commandos to battle the Red Skull's forces. However, during an attempt to finally capture Zola in the Austrian Alps, Barnes was caught in their ambush and plummeted hundreds of feet from a train. As no body was ever recovered, Barnes was then presumed deceased, but officially listed as missing in action.

Unbeknownst to his team, Barnes' experimentations allowed him to survive the fall, albeit with the loss of his left arm. Once found by the Soviet Union and HYDRA, Barnes was further experimented on, granting him superhuman abilities, and was subsequently brainwashed and armed with a new cybernetic limb in order to become their operative, known as the Winter Soldier. Over the next fifty years, he would eliminate anyone who posed any threat to HYDRA, including Howard Stark and his wife, Maria. Between all these assassination missions, the Winter Soldier would be put into a cryogenic stasis to ensure his longevity. In 2014, the Winter Soldier had been ordered by Alexander Pierce to assassinate Nick Fury, in order to ensure that all Pierce's schemes with Project Insight could go ahead. However, the Winter Soldier was challenged by Steve Rogers, which had triggered him to begin remembering his prior life.

In the wake of their Battle at the Triskelion, Barnes, free from his brainwashing, deserted HYDRA in order to remember his past and end his long, violent history. Two years later, Barnes was then framed for the Bombing of the Vienna International Centre, which claimed the life of T'Chaka, among many other innocent lives. While the Black Panther sought revenge for his father's death, Barnes had been repeatedly saved by Captain America, which sparked the Avengers Civil War as a team of Avengers, led by Iron Man was sent to capture him. However, they eventually learned that Helmut Zemo framed Barnes and reactivated his brainwashing, so that Zemo could reveal that Barnes had murdered Stark's parents years ago. Having just survived Stark's revenge attempt, Barnes was given amnesty in Wakanda by T'Challa and was placed in cryostasis, until all HYDRA's control triggers could be removed from his mind.

Barnes was eventually freed of his brainwashing by the efforts of Shuri. However, as Thanos had attempted to kill Vision for the Mind Stone, Barnes returned to combat to stop the Mad Titan's plans, receiving his new vibranium arm. Barnes joined T'Challa and the Avengers to help fight off the threat, only for Thanos to defeat them and assemble all of the Infinity Stones. Barnes was subsequently disintegrated as Thanos eliminated half of all life in the universe. In 2023, Barnes was resurrected by Hulk, as he had then participated in the final battle against Thanos' forces. In the aftermath of the battle, he attended the funeral of Stark with all the other heroes. Later on Barnes bid Rogers farewell, knowing of his true intention to travel back to the 1940s in order to live with Peggy Carter. Bucky was surprised when Steve returned with a resurrected Natasha.

Sharon and Bucky hooked up when she leaned that Steve and Natasha were expecting a child. After their night together, Sharon discovered that she was pregnant so she told him about the baby and told him that she didn't want the baby. After she had the baby and gave her to Bucky and he named her Stevie Barnes. While trying to figure out how to raise a baby, he got closer to Wanda who was helping him adapt. Once Stevie was taking along with Sarah, the two became even closer while trying to track down Stevie. The two eventually end up dating and having Rebecca Barnes. Bucky was once again taken by Hydra but he was reunited with Stevie and Sarah, he was forced to train them how to fight. He was so happy to be with his daughter again but upset that for the past five years that have been training his child and Sarah to fight. He was held by HYDRA and the Red Room until Stevie and Sarah were trained and Bucky came up with a plan to get them out of there.