Episode 5 of Marvel’s What If…? infects the world with a zombie plague, claiming many Avengers to the ranks of the undead, including Captain America: but just how strong is Zombie Cap? Despite the decay of their minds and bodies, the superheroes infected by the zombie virus retain their powers, meaning the super serum that gave Steve Rogers his powers still exists in his undead counterpart.

What If…? has explored how one vital change can alter the events of the entire MCU. Episode 5 opens with Hulk falling to Earth to warn of Thanos’ imminent arrival, only to find something terribly wrong. In this universe, when Hope Van Dyne sent Hank Pym into the Quantum Realm to find her mother, he found a plague-ridden Janet, who was then set loose on the world. Transmitted through saliva, the zombie plague spread faster than ever when the Avengers were infected as well. As one of the infected, Captain America would pose a serious threat to the survivors of the zombie plague, but just how strong is he? And why didn’t the super serum prevent Rogers from being infected in the first place?

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One might presume that enhanced durability would prevent Cap from becoming infected with the zombie virus, but based on What If…? episode 5, this is not the case. Regardless of the serum, Cap is ultimately infected, but his zombie counterpart is not as strong as one might initially believe. Although the infected superheroes still have functioning powers, they are still easily dispatched by those left uninfected. Sharon Carter and Okoye don’t have powers and they each manage to fight off zombie Avengers before falling victim themselves. Ultimately, Bucky defeats the Captain America zombie in What If...? without much of a fight.

Marvel What if why Bucky could let Captain America Steve die

Ultimately, an undead Captain America would be a serious threat to the average citizen looking to remain uninfected, but when faced with trained — and in some cases super-powered — adversaries, zombie Captain America does not stand a chance. While Sharon Carter falls victim to Cap, it takes all of two minutes for Bucky to use the shield against his former friend. This is surprising considering how evenly matched the two have been in the past. Episode 5 of Marvel’s What If…? makes it clear that most of the zombie Avengers (except perhaps the Scarlet Witch) are weaker than their formerly living components, including the first Avenger himself, Captain America.

The super serum injected into Steve Rogers enhanced his strength, agility, stamina, and durability — but he's not invulnerable, often depending on his fighting skills to defend himself. In the episode, Cap was bitten by a minuscule zombie Hank Pym. Since Pym sneaks up on Cap by shrinking, he cannot use his enhanced fighting skills to protect himself. Unlike Banner/Hulk, the serum does not make Captain America’s skin impermeable, meaning the infected saliva can breach his bloodstream. The zombie virus from the Quantum Realm is more potent (and foreign) than any sort of virus that a human immune system would have the ability to fight off, which could be why the serum did not afford Rogers protection.

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Marvel's What If...? releases new episodes Wednesdays on Disney+.

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