A new teaser for Marvel's 'Avengers: Doomsday' showcases an unexpected crossover, uniting characters from Wakanda and the Fantastic Four. The footage features Shuri and M'Baku interacting with Ben Grimm (The Thing), highlighting the integration of these distinct Marvel universes. This teaser, released ahead of the film's December 18, 2026, premiere, also hints at the return of other characters and franchises, building anticipation for Phase Six of the MCU.