While the upcoming "Avengers: Doomsday" (originally slated for May 1, 2026, and now pushed to December 18, 2026) faces a delay, MCU fans worldwide are still eagerly anticipating a historic moment. Reports suggest the film will draw inspiration from the animated series "X-Men '97" to officially introduce mutant characters, setting up a classic battle as its opening climax and paving the way for the X-Men's integration into the MCU.
According to well-known scooper MTTSH, "Avengers: Doomsday" is set to open with an an epic battle at the X-Mansion. Set photos reportedly show Sentinel debris scattered across the campus, hinting at an unprecedented conflict involving mutants.
MTTSH indicated that this sequence will not only mark the X-Men's debut but may also feature some Avengers members fighting alongside them. The visual style is expected to mirror the opening episodes of "X-Men '97," offering audiences a comprehensive look at the entire team and their powers. 
Earlier rumors suggested that "Avengers: Doomsday" would introduce some actors from the X-Men reboot; however, recent reports have refuted this, indicating that these characters might instead debut in "Avengers: Secret Wars." Given that both films have experienced scheduling delays, many character arrangements remain subject to change.
Separately, the social media account @UnBoxHD shared aerial footage from the set. While information is limited, the video clearly shows extensive battle damage and explosion marks, lending credence to the rumors.