10 Strongest MCU Heroes To Never Join The Avengers

Captain America is one of the most powerful heroes in the entire MCU, and is certainly one of the strongest Avengers ever. Had Bucky ever officially joined the team instead of just fighting side by side with them, he would have been right up there with him.

When Sergeant Barnes was captured during the War, he was experimented on, which allowed him to survive the fall from the train that should have killed him. Instead, he was found by HYDRA and experimented on further, bringing him as close to the physical condition of Steve Rogers as possible.

He also had his left arm replaced with a prosthetic at the height of what was technologically possible. He was even frozen in between missions to ensure he didn't age, thus keeping him in peak condition. He was designed to be the ultimate killing machine, and that's what he became.

Even when going toe to toe with Captain America, Bucky came out on top, and was even able to stop Rogers' vibranium shield in mid air, with one hand. Though Bucky may no longer be the Winter Soldier in his mind, he is still every bit as strong.