The Super Soldier Serum was heavily focused on during the events of The Falcon And The Winter Soldier. First created by German-born scientist Abraham Erskine and believed to be a thing of the past, the serum had been recreated by Dr. Wilfred Nagel who isolated it from Isaiah Bradley’s blood sample provided by the CIA.
Unlike Esrksine’s version which had plenty of side effects, Nagel’s version was much more advanced. New users were able to self-inject it instead of having it administered through the Vita-Ray Chamber as was the case with previous users like Steve Rogers. So far, a number of characters in the MCU have used the serum at various stages, achieving varying degrees of power.
Isaiah Bradley
Bradley was injected with the serum by the US military and assigned to the Korean War where his task was to eliminate the Winter Soldier. He was later imprisoned for three decades and after being freed, he settled in Baltimore.
Thanks to the serum, Bradley aged much slower than normal humans. Having been born in the 1930s, he was over 90 years old when he first met Sam Wilson but he looked like a man in his 60s. His other powers are unknown since he was never seen in combat. It should be presumed he has super strength too.
The Flag Smashers
The Flag Smashers stole 20 vials of the Super Soldier Serum from Dr. Wilfred Nagel and used eight of them, hiding the rest in the tombstone of Lukasz Kovaczsik. After taking the serum, all of them became incredibly strong.
For example, Karli Morgenthau sent the enhanced Bucky Barnes flying several feet with a single hit. She also got the better of Falcon and John Walker. Her punch caused enough blunt trauma to kill Battlestar. The serum appeared to have made the Flag Smashers bulletproof too.
John Walker
MCU’s most hated character at the moment debated whether to take the serum for a while. After being humiliated by the Dora Milaje, he finally decided to take it. Though the serum made him superhuman, he began making reckless decisions that eventually led to him being stripped of the mantle of Captain America.
An enhanced Walker was strong enough to fold a steel pipe with bare hands while fighting Dovich. During the fight outside the Global Repatriation Council’s facility, he moved a truck full of civilians while simultaneously fighting the Flag Smashers. And after breaking his arm during a fight with Sam and Bucky, he healed very quickly too.
Johann Schmidt aka Red Skull
Former HYDRA boss Johann Schmidt was the first-ever person to take the serum. However, the serum he took (made by Abraham Erskine) was still in its prototype phase and wasn’t meant to be used by a human yet. As a result, Schmidt developed special abilities but the skin of his face got damaged as a result.
Thanks to the serum, Schmidt became an extremely intelligent supervillain. His high IQ enabled him to not only find the Runestone and the tesseract but also harness the power in them. His strength was also boosted. He moved a big stone casket lid all by himself after three men jointly failed to do so.
Bucky Barnes aka Winter Soldier
Sergeant James Buchanan “Bucky” Barnes was an officer of the 107th Infantry Regiment during World War II when his squad was captured by HYDRA. He was then given the serum by Arnim Zola. He was later rescued by Rogers but lost his arm after a train fall. After being recaptured, he was brainwashed and turned into an assassin.
The serum gave Bucky incredible strength which he still has to date. He demonstrated his strength once again during the fight with the enhanced Flag Smashers in The Falcon And The Winter Soldier. Bucky also boasts of enhanced reflexes, enhanced agility, and durability, since his muscles are denser.
The 1991 Winter Soldiers
In 1991, a group of assassins was injected with the serum made by Howard Stark. They were meant to replace Bucky as the Winter Soldier and when tests were conducted on them, they proved to be much stronger. They had all the powers that Bucky possessed and were more skilled in martial arts too.
Unfortunately, the serum caused the assassins to be mentally unstable. When they began a riot, they were placed in the Cryostasis Chambers. Years later, they were murdered by Helmut Zemo.
Steve Rogers
Rogers was the first recipient of the perfected version of the serum. He was injected, and a short while after the procedure, he grew from 5’4′ to 6’2. His weight also increased from 95 lbs to 240 lbs. He also gained immunity from all earthly humans. Most importantly, he became perfect enough to become the hero known as Captain America.
The serum enabled Rogers to have a longer lifespan than normal humans. It also gave him immense strength. There was proof of just how strong he was when he pulled back a helicopter. He also managed to restrain Thanos’ hand. In addition to that, Rogers has enhanced senses and can heal very quickly.
Bruce Banner aka Hulk
As a scientist, Bruce Banner tried to recreate Erskine’s serum. However, he replaced the Vita Radiation with Gamma Radiation. When he administered the serum to himself, he turned into the Hulk. Since the gamma was stored in his body cells, he would turn into the Hulk whenever his heart began beating too fast. Later on, he learned to control his powers.
After the experiment, Hulk became one of the strongest beings on Earth. During his time in the MCU, he has managed to lift forklift trucks and tanks. He also held on to the debris of a falling building and acquired the ability to do super leaps, which enabled him to move very quickly.
