Captain America: Brave New World ended with a vague tease for Avengers: Doomsday. During a tense exchange with Samuel Sterns in The Raft, the villain warned Sam Wilson that "it's coming" and said he'd "seen it in the probabilities."
"All you heroes protecting this world. Do you think you're the only ones? Do you think this is the only world?" The Leader asked the hero. "We'll see what happens when you have to protect this place...from the others." Who or what are the "others"?
Well, some fans believe it might have been the Council of Kangs, especially as much of this movie was shot when Avengers: Doomsday was still called Avengers: The Kang Dynasty. We've also seen suggestions that it's simply the heroes (or villains) from another reality who will battle Earth-616's Mightiest Heroes when an Incursion occurs.
According to The Wrap, there was going to be a version of the Illuminati in Captain America: Brave New World. We met that group in Doctor Strange in the Multiverse of Madness, though the Scarlet Witch made short work of them on Earth-838.
The trade asked Captain America: Brave New World director Julius Onah about who made up the group and he responded, "I’m not going to say! I’m not going to say [Laughs]. Let’s just say things are purposely left vague in that post-credit for a reason."
Since then, scooper Alex Perez has shared the following:
There have been theories about Doctor Doom leading a group of Variants who are attempting to save the Multiverse, with at least one of them likely a version of Steve Rogers who is loyal to HYDRA.
We'll have to wait and see, though this and other comments from Perez have suggested Spider-Man: Across the Spider-Verse's Miguel O'Hara will be part of the team.
Talking more about the post-credits scene, Onah said, "That was always pretty much the post-credit scene, and I say that because we didn’t shoot that until our additional photography process, which was when we always knew we were going to do it, because we had this time period allocated to do it."
"And the goal was to make sure that we were doing it at a time which, because of the strikes, we weren’t writing, nobody was writing, where there was just a clearer picture of where things were going," he concluded.
Captain America: Brave New World is now playing in theaters.