The original Super Soldier Serum was created by Abraham Erskine (Stanley Tucci) while he was still living in Germany before escaping to America to get away from the Nazi party. Of course, we've all seen the movie, we know he went on to perfect his formula and give it to Steve Rogers.
For Banner, the serum, mixed with exposure to gamma radiation, grants him the curse-come-blessing of being able to change into the Hulk, but Blonsky's physiology changes in some much more sinister ways, turning him into the Abomination after mixing the super-soldier serum with Banner's own blood samples.
Alongside her rigorous training, Natasha Romanoff also has super-soldier serum pumping through her veins. This version of the serum does not grant her the same strength as Captain America, but it does allow Natasha to perform at peak human condition in regards to her stamina and strength.
Artificially Enhanced Physiology: Due to being injected with a prototype version of the Super Soldier Serum that was given to Captain America, his physical and mental abilities have been enhanced to beyond the peak of human potential, although some of his abilities may have dwindled with age.
Yes, Buck did have the super soldier serum. It's implied that Dr. Zola injected his version of the serum into Buck during his captivity from HYDRA during World War II, more exactly the events of The First Avenger.
After his transformation into The Unseen, Nick Fury now possesses the same Cosmic Awareness as the Watchers, which grants him the ability to observe different timelines, allowing him to see the past, present and even possible futures of every alternate timeline.
Bucky owes his youthful appearance to repeated cryo-freezes orchestrated by the Russians. He possesses no super powers and never received a form of the Super Soldier Serum as many assume, but continues to operate at peak human ability.
Nick Fury's Wife Is a Skrull, and He's Okay With That. Fury's wife, Varra worked for the rogue Skrull faction led by Gravik, which Fury was unaware of. Their romance was always an arrangement. Priscilla, Fury's wife, survived the Snap and mourned his absence for five years.
From 1940's Captain America Comics #1 (by Joe Simon, Jack Kirby, and Ed Herron), Rogers has stood firm as the world's foremost super-soldier and as the United States' very first Star-Spangled Avenger.
Bruce Banner is not a typical super soldier. He was a leading mind in biochemistry and Gamma radiation that happened to be manipulated by the MCU's General "Thunderbolt" Thaddeus Ross into tinkering with a replica of the original Super Soldier Serum.
Serum enhances the strength and ability of human. Now bucky was not weaker than John, but we can see the fact that even at his human level John walker had better training than Bucky. He was so good as fighting before even getting the serum. So he was able to fight better than bucky.
Thor. Thor, the god of Thunder, was undoubtedly the most powerful member of the original Avengers. His power continues to grow in the Marvel Cinematic Universe.
While Clint Barton has no superhuman powers (with the exception of the period when using Pym particles as Goliath), he is at the very peak of human conditioning. He is an exceptional fencer, acrobat and marksman, having been trained from childhood in the circus and by the criminals Trick Shot and Swordsman.
Luke Cage. During his time as an inmate, Luke Cage was experimented on to recreate the Super Soldier Serum that gave Captain America his abilities by Doctor Noah Burstein.
Bucky Barnes is getting a new arm in Thunderbolts it appears, and it could help set up Wolverine's Marvel Cinematic Universe debut. Known for his metal arm made from vibranium, Phase 4 delivered a surprise twist related to Winter Soldier's future.
Bradley also reveals in episode 2 that he beat Bucky so badly that his original arm was partly smashed and the formidable assassin was forced to retreat. Clearly, if Bradley's serum variant had weaknesses, they didn't compromise his strength. In the comics, Bradley's powers are more concisely mapped out.
Steve Rogers was the first and only recipient of Erskine's perfected serum, granting him superhuman abilities, curing all his medical ailments, and significantly increasing his height and physicality. It also increased his lifespan, allowing him to survive to be over one hundred years old.
In terms of raw strength, Captain America is typically portrayed as being stronger than the Winter Soldier, although the Winter Soldier's combat skills and agility can still make him a formidable opponent.
Popverse has been suspicious for some time, and the episode 'Beloved' confirmed it - James Rhodes is a Skrull. That's right, the same Rhodey who has fought alongside the Avengers as War Machine. Rhodey's behavior in the past few episodes has raised some eyebrows, including the moment where he fired Nick Fury.
Priscilla Fury is not a character in the Marvel Comics—she's been created just for the MCU. That being said, it's worth noting that Nick Fury does have a decades-long, on-again, off-again, torrid romantic affair with someone: the Contessa Valentina Allegra de la Fontaine.
Raava was a member of the Skrull Resistance, who was ordered by Gravik to impersonate James Rhodes and get closer to President Ritson. As Raava was engineering the political tensions between the United States and Russia, she came into conflict with Nick Fury and stripped him off of his authority.
Bucky Barnes, like Steve Rogers, has lived for several decades due to cryogenic freezing and the super-soldier serum. Bucky's life expectancy could potentially surpass Steve's 116 years, depending on circumstances.
Despite possessing no enhanced traits such as Captain America or any superhuman abilities, Bucky is still alive, his body partially preserved by the freezing waters, and is able to be revived. Along with the loss of his left arm, he has brain damage and amnesia as a result of the explosion and his time in the water.
Bucky was born on March 10, 1917, so he was already older than Steve, who was born on July 4, 1918, even before they became enhanced. Further, Captain America was frozen and preserved as he was in 1945 without thawing for nearly seven decades before he was revived.
