The Multiverse of Madness Makes Doctor Strange's Abandoned Villains Even Better
Despite replacing him with Scarlet Witch, Doctor Strange in the Multiverse of Madness teases Nightmare's multiverse powers in future sequels.
After Doctor Strange in the Multiverse of Madness didn't appear as the original villain Nightmare in the Doctor Strange sequel, he could still be a stronger villain in future MCU movies. Doctor Strange in the Multiverse of Madness includes two important Doctor Strange villains, Baron Mordor and Shuma-Gorath (aka Gargantos), but neither is the main threat of the Maestro in the film. Instead, it was Scarlet Witch who put the entire multiverse at risk as she went from beloved Avenger to unhinged interdimensional villain.
Original Doctor Strange director Scott Derrickson was set to direct Doctor Strange in the Multiverse of Madness before Sam Raimi took over as director. Scott Derrickson's original plans for Doctor Strange 2 had a more Lovecraftian tone, didn't focus too much on multiverse variants, and featured Nightmare as a villain— Maybe even the main villain. In the end, Nightmare was cut from the script entirely, but Sam Raimi's film version not only set the stage for Nightmare's eventual debut, but also teased how powerful he'd become when the MCU decided to bring him in.
Multiverse Of Madness Sets Up The MCU’s Nightmare
Sam Raimi's Doctor Strange and the Multiverse of Madness Established Dreams are portals to alternate universes. Sinister Strange and Scarlet Witch are able to turn it into a weapon called "Dreamwalking", the evil Strange kills multiple Strange mutants by driving them to death, while Scarlet Witch uses her mutant body to slaughter the Illuminati and Captive American Chavez. Given that Nightmare's powers are based entirely on dreams and the subconscious, it's possible that future MCU versions will take a similar route and introduce Nightmare the Fear Lord as a powerful multi-villain.
Nightmare Could Be More Dangerous Than Scarlet Witch
While Scarlet Witch uses sleepwalking as a weapon to wreak havoc in alternate universes, her entry into the multiverse is only a means to an end. Wanda's main goal is to retrieve her children from an alternate reality, and it's only necessary to kill heroes like the Illuminati of the 838 universe if they stand in her way. Nightmare's main goals, on the other hand, usually focus first on invading other universes and merging them with his Nightmare realm. Unlike Scarlet Witch and Menacing Strange, Nightmare can easily enter all realities through people's dreams without using the Book of Darkness, which didn't survive Doctor Strange 2.
Nightmare may also be more dangerous than Dormammu Himself, because he probably doesn't need to brainwash wizards to make them his loyal followers. In order to achieve what Dormammu couldn't, the only thing Nightmare might need is an unstable multiverse, which has existed since Phase 4. In Marvel Comics, Nightmare is a primordial entity, like Thor: Love and Thunder's Eternal Monk-The Darksider of the Legend of the Red and the Ten Rings. Since Phase 4 has introduced them as well - and with Werewolf By Night debuting as the guardian humanoid of the Nexus of All Realities - Nightmare now has a number of possible ways to begin his multiverse conquest in the MCU.
How Nightmare Can Fit The MCU Multiverse
While Doctor Strange in the Multiverse of Madness has Nightmare making his MCU debut in the near future, there may not be enough room for him in the multiverse saga. Jonathan Majors' Kang the Conqueror has become a major villain in the multiverse saga, and films like Rocky and Ant-Man and the Wasp: Quantum of Madness have focused on cementing his power and ambition superior. Introducing Nightmare at the same time could be a distraction from Kang's MCU journey, even more so in a movie as crowded as Avengers: Dynasty Kang and Avengers: Secret Wars. Given their diverse objectives, Regardless, Kang's multiple appearances in the MCU throughout the series may overshadow Nightmare.
Doctor Strange 3 likely won't arrive until after Avengers: Secret War, so Doctor Strange and Kree's mission to fix the multiverse invasion will likely skip Nightmare's involvement, at least until Kang the Conqueror stops. However, Nightmare will likely continue to be teased in other projects. For example, Ironheart's magical villain, The Hood, can provide some insight into supernatural entities such as Mephisto, Dormammu, and Nightmare himself. Agatha: The Chaos Conference could expand Agatha Harkness' history to reveal a possible connection to the Lord of Terror. It might be a long time before Doctor Strange in the Multiverse of Madness hits theaters, but Nightmare's MCU debut is well worth it.