After 10 years, the Marvel Cinematic Universe has completed its 22-film Infinity Saga (23 if you count the Spider-Man: Far From Home epilogue). Several big stories and events from Marvel Comics served as the inspiration for the films, including origin stories, first appearances, and bigger crossover events such as Civil War, Age of Ultron, and The Infinity Gauntlet to name a few.
Now, looking to the next 10 years of MCU films, which Marvel Comics stories/events will be used next, as Marvel Studios continues to interweave the overarching narrative they're so good at telling? Here are a few of the bigger narratives that seem exciting and/or likely.
The Kree/Skrull War
The Kree/Skrull War is a classic Marvel Comics tale, featuring the Avengers becoming caught in the middle of two alien races that have long been at war. The Kree Empire is a race of technologically/scientifically advanced species, led by an A.I built from the deceased members of their best of brightest ancestors known as the Supreme Intelligence (They're also responsible for the creation of Inhumans as well as Captain Marvel.) The Skrulls are a race of shapeshifters who are extremely efficient as infiltrating planets and power structures, corrupting them from within to better aid in conquest. Both the Kree and the Skrull see Earth as a key planet to stage attacks against each other, which came to a head during this storyline. The Captain Marvel film has already sown the seeds and shown their ongoing war, albeit depicting the Kree as the more oppressive race of the two, with Carol Danvers aiding refugee Skrull families at the end of her debut film. It would be interesting to see the war continue in the upcoming Captain Marvel sequel, coming in 2022.
House of M (Reversed Concept)
It's been revealed that the WandaVision series coming to Disney+ and Doctor Strange and the Multiverse of Madness will be closely tied together (Wanda will be in the Doctor Strange sequel). The prevailing theory is that Wanda's powers will get out of control, resulting in Strange's intervention and mayhem within the multiverse and reality itself. If that is to be the case, it would certainly be interesting to see a reworked version of the House of M storyline. In the storyline, Wanda reshapes reality in her image so that everyone gets their heart's desire. When the harshness of her reality comes back (the deaths of Vision and her children), Wanda blames mutant-kind, removing several mutant powers across the world and inhibiting the X-gene, causing mutants to nearly go extinct. As mutants have yet to be revealed in the MCU (and now can), it would be really exciting to see Wanda's tampering with reality to be the cause of the mutant's existence rather than its demise.
Avengers Vs. X.Men
Regardless of whether or not a reversed concept House of M brings the X-Men into the MCU, they will arrive eventually as Disney now owns the rights to the franchise. Once their introduction happens, it would be incredible for Marvel fans everywhere to see the new mutant team take on the already established Avengers in a blockbuster crossover for the ages. In Avengers vs. X-Men, the Avengers and X-Men fight over the latest mutant to host the Phoenix Force. The Avengers are concerned about its capacity for destruction, while the X-Men see it as a possibility for creation and the potential rebirth of their kind (see House of M.) Such a powerful entity is the perfect reason for the teams to clash, and would almost certainly translate well to the big screen.
War of the Realms
One of the bigger and more well-received crossover events in the last few years, War of the Realms, saw villains and armies unite under Malekith the Dark Elf to dominate all 9 Realms. Heroes from across the Realms, including the superheroes of Earth, join Thor and Asgard in fighting back to keep the 9 Realms from descending into chaos. While the MCU version of Malekith has already been featured and defeated in Thor: The Dark World (to very poor reception), perhaps the more popular Goddess of Death Hela could make a return to unite the more sinister characters across the Realms. The event also culminated in Thor also claiming the throne as king of Asgard as well once the Realms were saved. A War of the Realms film could take its cue from Captain America: Civil War, where Cap was the focus, yet featured several other Avengers as well. War of the Realms could be similar as a Thor sequel, but also have other heroes join the God of Thunder in his battle. Thor could likewise claim the throne of Asgard as well, a title he has long resisted and deferred to others in the MCU.
Annihilation
Expanding on the idea that Marvel Studios would continue to flesh out the more cosmic side of the MCU, Annihilation would be a great story to adapt or take reference from. Not only would it feature a new universal threat in Annihilus and his Annihilation Wave from the dark reality known as the Negative Zone, but also provide a means for Nova to be featured, and potentially the Fantastic Four. In Annihilation, the Annihilation Wave attacks Xandar and the Nova Corps, leaving all but Richard Ryder, a human Centurion, alive. Seeing as how Thanos has already destroyed Xandar just before the events of Infinity War to obtain the Power Stone, there's already a precedent for Ryder to be the last Nova in service. Furthermore, the Negative Zone is the perfect vehicle to introduce the MCU Fantastic Four. The First Family were initially scientists and explorers. Perhaps they sought to pioneer a newly discovered Negative Zone in the MCU's early days that have been trapped all this time? It could be that Annihilus' attack provides a means for them to get out and save the day. In any case, Annihilation would no doubt be an epic tale of galactic proportions that would be sure to entertain audiences.
Avengers: Secret Wars
Last but not least, the perfect comic event for the next Avengers film would have to be based on Secret Wars from 2015. In Secret Wars, the standard Marvel Universe and the Ultimate Universe (where Spider-Man Miles Morales resides) are the last Earth's in the universe to collide and become erased like all the others recently have. However, a plan to survive is formed by Doctor Doom, Doctor Strange, and the Molecule Man. Instead of the Earth's becoming destroyed, a new world is formed known as Battleworld: a patchwork realm of fragments from the destroyed Earths, ruled by God Emperor Doom. This would be an incredible film to watch, seeing everything fans know of the MCU get turned on its head and mixed with other realities. Thanks to WandaVision, the Doctor Strange sequel, and the upcoming animated What If...? series, audiences will have already been given a taste of alternate realities, events, and characters so Secret Wars shouldn't be too far out of a concept for them to grasp. An MCU Secret Wars would possibly rival the epic that was Infinity War/Endgame.
Of course, there are nearly countless stories and events from Marvel Comics that the MCU could utilize. Some of the ones listed here could be part of it over the next 10 years, or none of them will be. In the end, it won't matter due to the simple fact that Marvel Studios has proven that their ideas and plans are more often than not extremely solid, surpassing the expectations of its large audience of fans beyond even their wildest ideas and theories. However, that's not for a lack of trying. It's doubtful that fans creating theories are going to stop any time soon (see list above).