WARNING: The following contains spoilers for What If...? Season 1, Episode 3, "What If... the World Lost Its Mightiest Heroes?," now streaming on Disney+
Thanks to the innate nature of What If...?, plenty of dark alternative scenarios can be set up for the Marvel Cinematic Universe to encounter. Perhaps most intriguing is the fallout that will inevitably come because of the latest episode's events, which saw Hank Pym wipe out many of the founding Avengers before they ever became a team -- and inadvertently set his world on a far darker path.
The climax of "What If… The World Lost Its Mightiest Heroes?" sets up a genuinely dangerous and interesting world, where the lack of major mighty heroes that would have formed the original Avengers likely leads to a far more destructive reality.
In the world introduced in "What If… The World Lost Its Mightiest Heroes?," the Avengers are largely wiped out before they can ever formally become a team. After Hank Pym becomes Yellowjacket and goes on a vengeful crusade against Nick Fury, many of the foundational MCU heroes are killed off in brutal fashion. Fury can only defeat Pym and capture him thanks to the help of Loki, who -- with Thor dead via an arrow to the chest -- has become the uncontested King of Asgard. With an army at his back and the Casket of Ancient Winters in his hands, Loki brings the Warriors Three and an entire army to Earth to find vengeance for Thor's demise.
Although Fury staves off a full invasion after revealing Pym's guilt, Loki decides he sees potential in conquering the Earth. Taking to the floor of the United Nations, this Loki variant deploys the same kind of speech he frequently said in the MCU's core timeline, arguing that humanity's true purpose is to kneel to its betters, such as Loki and his ilk. Fury prepares for an inevitable confrontation between himself and Loki and decides not to let the idea of the Avengers die just because the Mighty Heroes he'd hoped to recruit had been taken out. Finding a frozen Captain America hints at the presence of Steve Rogers in the upcoming team, and Fury's decision to call Captain Marvel back to Earth gives him an additional powerhouse to work with.
But there are other power players presumably still active in this reality, despite the changes that have already affected it. It's highly unlikely a nation like Wakanda will simply adhere to the potential threats that Loki will likely try to use to force the world in line, setting up Black Panther to fight against him. Fury will likely keep SHIELD prepared to contend with Loki and his forces, which might be complicated by the still active Hydra splinter cell at the heart of SHIELD and still unrevealed at this point in the timeline. While the deaths of the Avengers might have prevented the Battle of New York and the creation of Ultron, figures like Justin Hammer, Whiplash, A.I.M. and the Dark Elves have not been stopped in the slightest. Odin's eventual death will also unleash Hela into the universe.
Earth is poised for a serious series of conflicts, which will only be complicated further by the lack of heroes to defend humanity. Other heroes will also likely never take up their mantles (Scott Lang probably won't find the Ant-Man suit without Hank Pym's involvement) or be more cautious about their potential roles as protectors (in a world where Tony Stark died at his lowest moments in Iron Man 2, it's unlikely Peter Parker saw as much appeal in becoming a hero). The world of "What If… The World Lost Its Mightiest Heroes?" deserves a revisit at some point, just to see how a world on the verge of a major conflict against Loki and an Asgardian army instead of the more chaotic Cthuari actually plays out.
To see Earth's Mightiest Heroes fail to form in the MCU thanks to Yellowjacket, the third episode of What If...? is streaming now on Disney+.