A trailer for "Avengers: Doomsday" has been released, featuring a large cast and introducing Doctor Doom, with some outlets reporting that the character is played by Robert Downey Jr. The trailer appears to showcase a significant battle, bringing together major heroes in the Marvel universe. The release of the trailer has also drawn attention to other elements, including a new look for H.E.R.B.I.E. and a poster for the film.