Natasha Romanoff's adoptive family in Black Widow includes Alexei Shostakov a.k.a. Red Guardian, the Soviet Union's answer to Captain America and the closest thing that Nat has to a father. Red Guardian has super-strength to rival that of Captain America, flexing his powers by lifting a tank and scaling walls with ease, but the details of exactly how he got his powers are left vague.

Red Guardian was at one point the USSR's own celebrity superhero, with action figures made in his image and a brightly-colored suit and throwable shield. After the collapse of the Soviet Union in the 1990s, however, he was assigned the rather more mundane task of operating as a sleeper agent in the United States. To help sell his false identity he was paired up in a fake marriage with Melina Vostakoff and given two daughters: Natasha Romanoff, who had already been through some of her Widow training in the Red Room, and General Dreykov's more recent acquisition Yelena Belova, who was just three years old when Red Guardian's mission began.

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Alexei's superpowers are showcased in Black Widow's thrilling opening sequence, as he uses his enhanced strength, speed and durability to help the family escape from the authorities after their cover is blown. 21 years later he is locked up in a remote maximum security prison (a consequence of offending Dreykov) and spends his days bragging about his past glories as the Red Guardian. But what happened to Alexei in his life before those glory days, besides the unfortunate incident with his father peeing on his hands to stave off frostbite? Here are the most likely explanations for how Alexei Shostakov gained his superpowers, in order of probability.

A Soviet Super-Soldier Serum

Steve Rogers after receiving Super Soldier Serum in Captain America The First Avenger

Whenever a new super soldier appears in the Marvel Cinematic Universe, it can generally be assumed that they're the result of someone attempting to recreate Abraham Erskine's super soldier serum. This serum was used to turn Steve Rogers into Captain America, but Erskine was assassinated immediately afterwards and his knowledge was lost. Instead of creating an entire army of super soldiers, the United States only had one. Attempts to replicate the super soldier serum have had mixed success and have created numerous variations of the super soldier ideal, ranging from the botched results of the Red Skull's super soldier serum (which gave him super-strength, but also gave him a monstrous appearance) to the differently botched results of Bruce Banner's super soldier serum (which turned him into the Hulk).

In the MCU, Red Guardian is the first and only Soviet Union super soldier, and was created to rival the military strength and propaganda potential of Captain America. If he was given his powers via a super soldier serum, then the Soviets could have obtained it from a number of possible sources. Perhaps HYDRA gifted the Soviets a dose of the same Winter Soldier serum that they used to turn Bucky Barnes into an unstoppable killing machine. Alternatively, scraps of Abraham Erskine's original research could have been discovered by the Soviets after the Allied victory in World War II, or they could have cooked up a super soldier serum entirely of their own design.

A super soldier serum would certainly explain Red Guardian's larger-than-life personality, as one of the most consistent effects of the serums is to amplify a person's essential nature. For Steve Rogers, the serum highlighted his compassion and heroism. For Red Skull, it amplified his evil. In Red Guardian's case, the super soldier serum apparently failed to make him obedient and unquestioning, and instead magnified both his braggadocious personality and his fierce affection towards those he considers family.

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"Brutal Experiments"

Marvel Comics Red Guardian Origin Story

In his Marvel Comics origin story, Alexei Shostakov doesn't actually have any superpowers. He was chosen to be the Red Guardian because of his already impressive career as a test pilot, and cut off from his former life (including Black Widow, who in the comics was his wife rather than his daughter) and reassigned to the role of the Soviet Union's greatest soldier and mascot. He was once a good man, but he became ruthless and single-mindedly fixated on proving himself to be stronger than Captain America. Though Alexei may not have had actual superpowers, it was suggested that he had been through some kind of scientific process in order to make him the ultimate soldier.

After recognizing the Red Guardian as her former husband in The Avengers #44, Natasha lamented that, "They changed him somehow... made him crueller! He seemed hardly the same man I once loved." The Official Handbook of the Marvel Universe's entry on Alleksey Lebedev, the first Red Guardian, reveals that there was more to Alexei Shostakov's transformation into the Red Guardian than just training and brainwashing. Lebedev's biography concludes by saying that "Alleksey allegedly died during the 1950s purges, opposing the brutal experiments that eventually created his successor, Alexei Shostakov." The MCU's origin story for Red Guardian could include its own variation on these "brutal experiments," which go beyond the simple injection of a super-soldier serum and into even darker territory.

Mutant Genes

Black Widow Red Guardian fighting stance

The Marvel Cinematic Universe has already started to tease the idea of mutants, which were previously off-limits but can now begin to be incorporated due to Disney's acquisition of 20th Century Fox. WandaVision retconned Wanda Maximoff's origins to reveal that while the Mind Stone may have amplified her latent powers, she actually performed acts of magic long before she volunteered for HYDRA's experiments. This new origin story was linked to Wanda's destiny as a prophesied figure called the Scarlet Witch, and the word "mutant" was never explicitly used. However, it opened the doorway for more MCU characters to have innate superpowers resulting from their mutant genes.

In Black Widow it's revealed that the baby girls who are taken away from their families and trafficked into the Red Room were specifically selected because of their genetic potential. Alexei Shostakov's selection as the Red Guardian could have been born out of similar reasons. If he had a latent X-gene, this could have been exploited through experimentation, brainwashing and drugs to bring his innate mutant superpowers to the surface.

Related: Red Guardian vs. Captain America: Which Super Soldier Is Stronger

Life Model Decoy

Red Guardian Toy Black Widow

As Loki recently proved, you can never be quite sure if a character in the MCU is organic flesh and blood, or simply a robot in disguise. Agents of SHIELD had a major story arc involving Life Model Decoys - hyper-realistic robot androids designed to replicate a human's appearance and personality so accurately as to be indistinguishable from the real thing. However, they're not limited to human-level strength, so Red Guardian being an LMD would explain his unnatural abilities. In Marvel Comics, Alexei Shostakov was replaced with a Life Model Decoy after sacrificing his life to save Captain America. However, if Black Widow's Red Guardian was a Life Model Decoy then he probably wouldn't have to deal with the very human problem of struggling to fit into his old costume.

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