Summary
- Avengers: Secret Wars will likely draw inspiration from the 2015 comic story, which features characters from all corners of the Marvel universe.
- Key characters like Molecule Man, Miles Morales, and Black Swan are yet to be introduced in the MCU, but they play integral roles in the Secret Wars narrative.
- Doctor Doom takes center stage as the sympathetic arch-villain, offering a power dynamic that sures other MCU villains, and he could be introduced in the MCU's Fantastic Four reboot.
Assuming this inspiration will translate to a relatively comic-accurate adaptation, many of the MCU's most well-established characters already have pivotal roles lined up. Among these are Thor, Doctor Strange, Peter Parker, and Black Panther, to name a few. Yet there are many other characters pivotal to the narrative of Secret Wars that have yet to be introduced in the MCU - and time is running short.
Reed Richards, who is central to the Secret Wars story, was introduced in Doctor Strange in the Multiverse of Madness and so has technically already been introduced in the MCU.

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10 Molecule Man Is At The Center Of It All
Molecule Man Could Be Introduced In Doctor Strange 3
It is hard to see how Avengers: Secret Wars can go ahead without the character that constitutes the MacGuffin of the whole arc. Molecule Man is the nucleus of God Emperor Doom's Battleworld, the means of its creation, and the source of Doom's godlike powers in the comics. As the source of Doom's godhood, it also falls to Molecule Man to provide the means of his defeat.
Ms. Marvel's Iman Vellani has posited a compelling theory that replaces Molecule Man with a "good" Kang variant, while another "evil" Kang variant fills the role of the Beyonder.
9 Miles Morales' Kindness Changes The Course Of Fate
Miles Could Be Introduced In Spider-Man 4
It is very possible that Avengers: Secret Wars will be the stage where Miles Morales is finally introduced to the MCU. As the Spider-Man of the "Ultimate" universe in Marvel Comics (a universe distinct from Earth-616), Miles Morales is brought into the main timeline through the events of Secret Wars in the first place. He also, however, plays a central role in bringing Molecule Man over to the side of the heroes.
In Secret Wars, Miles and Peter Parker are tasked with infiltrating Doom's repurposed castle, which now secretly houses Molecule Man. Upon discovering the relatively frivolous character at the center of the Battleworld, Miles is the one to offer him some food without a second thought. This is a kindness that Molecule Man keeps in mind before he essentially turns on Doom to lend aid to Morales' plight. This also sets Miles on a course to becoming a heroic main character of whatever universe emerges in the MCU's soft reboot.
8 Black Swan Helps Turn Doom Into A God
Black Swan Could Be Introduced In Doctor Strange 3
Black Swan is the most prominent member of an order of the same name - the Black Swans. Their whole MO surrounds the worship of Doom - whom they call Rabum Alal - and his attempts to save the Multiverse. As a vessel of exposition, there is no doubt that Black Swan could be replaced in the cinematic adaptation of Secret Wars. Yet her true purpose as a representative of the Black Swans is more consequential.
In order to build his power, Doom formed a religion around himself, with the Black Swans being his worshipers. His rise to ultimate power included the exploitation of these worshipers, whom he would deploy in his mission to destroy the Molecule Men of the Multiverse. As the God Emperor of Battleworld, Doom utilizes Black Swan as a minion to fight against the heroes (specifically Star-Lord) as they carry out a multifaceted plan to bring him down.
7 Cyclops Is The Most Important Member Of The X-Men
Cyclops Could Be Introduced In Deadpool 3
While Cyclops' appearances in Fox's X-Men franchise have been relatively lackluster, Scott Summers reaches an inordinate level of potential in the Secret Wars comic as he absorbs the Phoenix Force in a last-ditch attempt to stave off the final incursion. While this is a doomed endeavor, he is one of the few X-Men to live on in the Battleworld. It is there that he comes up against Doom - who proceeds to destroy Summers despite the Phoenix Force in an exceptional show of power.
Marvel will be forging ahead with its own X-Men stories post-reboot, but their arrival has already preceded the events of Avengers: Secret Wars. While both attempts at depicting the Dark Phoenix storyline have ended in failure, this is a chance for Marvel to tell its own Phoenix Force story in another context, with its power having already been pre-established thanks to Fox's X-Men franchise. It also gives Cyclops the chance to take center stage - even if only to die a heroic death.
6 Valeria Richards Is A Reluctant Doom Ally
Valeria Could Be Introduced In Fantastic Four
Though it involves just about every Marvel character that existed, Secret Wars is ostensibly a Fantastic Four story with Reed Richards and Doctor Doom's iconic rivalry at its core. Some of its most heart-wrenching moments come with the fact that, in Battleworld, Richards' family has been "stolen" by Doom, with Valeria being a "Von Doom" rather than a "Richards." Valeria Richards is also, along with the rest of Reed's family, lost in the Multiversal collapse, providing a tragedy for Reed to wrestle with.
Short of simply being a motivation for Richards, however, Valeria plays a central role in Battleworld as Doom's biological daughter with Sue Storm. In it, she is tasked by Doom to seek out the interlopers of his new world. While stopping short of outright betraying her father, Valeria proves her virtuous nature by failing to inform him of Peter Parker and Miles Morales' infiltration of his castle and expressing regret at her father's brutality.
5 Johnny Storm Is Battleworld's Sun
Johnny Storm Will Be Introduced In Fantastic Four
While Molecule Man is at the center of Doom's Battleworld, Johnny plays a comparable yet more tragic role by becoming Battleworld's living sun. As Fantastic Four approaches, investment in Marvel's first family will be at an all-time high by the time Avengers: Secret Wars rolls around. The tragic fate of Johnny Storm will, therefore, hit close to home, as his small yet central role in providing light and warmth to Doom's patchwork planet will drive home the dire straits that the MCU's heroes will be attempting to rally against while also helping to illustrate the uncanny nature of Battleworld.
4 Ben Grimm Is A Living Wall Against The Deadlands
Ben Grimm Will Be Introduced In Fantastic Four
In a similar fate to Johnny Storm, The Thing of Doom's Battleworld has been repurposed as the Shield - a sentient barrier against the Battleworld's most dangerous realms. These realms are host to hordes of Marvel zombies and Annihilus' Annihilation Wave, which are feared even by Doom and his powerful subordinates. In the comics, Thanos is the one to convince Grimm to rise against Doom, thus breaking the Shield and leading to a fight between the colossal Grimm and a Franklin-piloted Galactus: a scene that begs for a big-screen adaptation.
3 Galactus Is Reduced To A Plaything
Galactus Could Be Introduced In Fantastic Four
While it is unclear whether Galactus will be the main villain of Marvel's Fantastic Four, the colossal world-eater is one of the many features of Doom's Battleworld used to convey just how powerful God Emperor Doom has become. While Galactus is a godlike entity in the main Marvel universe, in Secret Wars he is merely a "toy" used by Doom's children, Franklin and Valeria. His inclusion in Avengers: Secret Wars would have to follow his being established as the cataclysmic threat of Fantastic Four to hammer home the sheer power that Doom has attained.
2 Susan Storm Plays An Important Narrative Role
Sue Storm Will Be Introduced In Fantastic Four
The variant Sue Storm of Battleworld is God Emperor Doom's wife and ally throughout the events. As his partner, Sue's interactions with Doom help to humanize him as his confidence in his authority falters. Compared to other main players in the Secret Wars story, Sue plays a smaller role but is still integral to its narrative. Positioning this variant of Sue Storm as Doom's wife comes with a messy host of implications for Reed Richards - and the audience - to wrestle with as the tragic fate of the Fantastic Four is laid bare.
1 Doctor Doom Is The Sympathetic Arch Villain Of Secret Wars
Doctor Doom Could Be Introduced In Fantastic Four
While Kang is ostensibly the arch-villain of the MCU's Multiverse Saga, Doctor Doom is the only candidate for the role in Avengers: Secret Wars. God Emperor Doom is Doctor Doom at his most powerful, and it is his relationship with Reed Richards that drives the most compelling part of the narrative in Secret Wars (aside, perhaps, from the epic battles between variants). With that in mind, he will almost certainly have to be introduced in the events of Fantastic Four, in whatever capacity, before he wrests control of the entire Multiverse as its god.
In of sheer power, he blows all other MCU villains out of the water. Making short work of the Phoenix Force, Infinity Gauntlet, and the combined might of several of Earth's Mightiest Heroes before a Molecule Man-empowered Reed Richards is the one to finally bring him down. As for his motivations, he is every bit as sympathetic as Thanos ever was, wishing to save the Multiverse and even dwelling on his own flaws as its new ruler. Whatever happens, Avengers: Secret Wars should finally be the movie to do Doctor Doom justice.