Marvel's official cast announcements and promotional materials, including footage from the Avengers: Endgame re-release and SDCC panels, have established a large ensemble featuring Robert Downey Jr. as Doctor Doom, the Fantastic Four, multiple X-Men actors, Thunderbolts members, and MCU veterans such as Thor, Loki, and Sam Wilson’s Captain America. Directors Joe and Anthony Russo have explicitly teased further unannounced appearances tied to the multiversal story, fueling trader focus on high-probability returns like Mark Ruffalo’s Hulk alongside speculation around figures such as Benedict Cumberbatch’s Doctor Strange or Tom Holland’s Spider-Man. With the December 18 release approaching, ongoing marketing and any late guild or studio confirmations could shift implied probabilities on specific character markets.