At the end of The Marvels, the audience sees Monica Rambeau (Teyonah Parris) closing the wormhole opened by Dar-Benn (Zawe Ashton) that poses a risk to the fabric of space and time, causing a rift in the space-time continuum. Toward the end of the movie, Monica explains to Captain Marvel (Brie Larson) and Ms. Marvel (Iman Vellani) that the only way to close it is from the inside. She uses the powers that her teammates charged her with to close it, but she is stuck on the other side of the wormhole—a different dimension that is not immediately explained to the audience. The post-credits scene of the movie shows us where exactly she went.
In the post-credits scene, Monia wakes up in a sterile laboratory bed and sees her mother, Maria Rambeau (Lashana Lynch), who is believed to be dead. As we saw in episode four of Wandvison, the audience sees Monica return from the Blip (Thanos’ snap that wiped out half of the Earth’s population). She wakes up in an empty hospital room and finds out that her mother passed away from cancer and didn’t have the chance to say goodbye to her.
She cries and tells her mom she’s missed her, but Maria doesn’t recognize her daughter. After they talk, Beast (a popular character from the X-Men) explains to her that she is in a different reality. Her mother gets up from the chair she was sitting in and is donning a red-and-white superhero costume, which she’s never worn before.
To those who are not Marvel connoisseurs, it may be hard to pinpoint who this dimension’s Maria Rambeau is supposed to be. Her costume looks similar to the character, Binary, who is a Carol Danvers variant from Earth-616, according to Marvel Fandom. It’s still unclear exactly what her role will be in the future of the MCU, but Marvel head Kevin Feige has stated in the past that the X-Men will be coming to the MCU, and it was hinted at when it was revealed that Kamala Khan is a mutant. Beast’s appearance in the post-credits scene is the latest hint of the X-Men in the MCU after we were given Patrick Stewart’s Professor Xavier in Doctor Strange and the Multiverse of Madness.