Rumors surrounding Avengers: Doomsday continue to fuel fan theories, with new alleged plot details suggesting that Steve Rogers’ decision at the end of Avengers: Endgame may have triggered the multiverse crisis at the center of the upcoming Marvel Studios film.

While the claims remain unverified, they have gained attention following comments from director Anthony Russo, who reportedly confirmed that Steve’s choice to remain in the past with Peggy Carter could have consequences that ripple across realities.

According to fan theories built around the alleged revelation, Steve and Peggy’s life together may not have unfolded in the same timeline fans assumed. One circulating theory suggests that Loki helped the couple move to Earth-828, a reality where Steve could live peacefully without creating another version of himself in that universe.

Another theory proposes that after discovering the damage caused by the timeline shift, Steve sought help from the Fantastic Four. Together, they allegedly traveled to Earth-616 — the main Marvel Cinematic Universe reality — to warn the Avengers about the growing multiversal threat.

The rumors also tie Steve’s actions to Doctor Doom’s motivations. Some fans speculate that Doom’s anger is not only connected to his long-standing rivalry with Reed Richards but also to the destruction of his own family, allegedly caused by the multiverse disruption linked to Steve’s decision.

Meanwhile, other post-credit scene descriptions have teased possible appearances from Loki, Bruce Banner and the Time Variance Authority (TVA).

One scene reportedly shows Steve and Peggy’s quiet life interrupted by a visit from Loki, who tells them he may be able to help before the screen cuts to black. Another sequence involves Bruce Banner, who is said to be isolated while working on a gamma-radiation suppressor before Doctor Doom arrives and forces him to transform into the Hulk.

The rumors further claim that Doctor Doom could target the TVA itself, destroying the organization before confronting Loki at the Citadel and potentially taking his powers.

Additional speculation suggests that the film’s ending could show the TVA discovering multiple realities colliding, referencing different Marvel universes — including Fox’s X-Men films, previous Fantastic Four adaptations — before delivering a warning that the multiverse is collapsing.