Random House will publish What If… The Multiverse Was Doomed? on 4 August 2026, a novel by DaVaun Sanders that serves as the finale to its Marvel What If…? book series and offers a preview of the multiversal stakes expected in the forthcoming film Avengers: Doomsday. The story follows Doctor Doom rampaging across the multiverse in search of Franklin Richards, whose reality-altering powers he wants to seize, prompting America Chavez to recruit a team of heroes from different dimensions to stop him, echoing the plot beats anticipated in the Doomsday film.

Chavez's team includes Loki, Scarlet Witch, Kitty Pryde and a version of Moon Knight who hosts the Venom symbiote, brought together to protect Franklin and thwart Doom's plans. Author DaVaun Sanders told Polygon that America Chavez's role was central to the book, giving the often-criticised character a chance to answer a call others avoided. Polygon shared an exclusive excerpt set a decade after Thor's death, in which an alternate Loki, now worthy of wielding Mjölnir, struggles to raise his niece Quinn while she pushes to become a hero herself, with the extract hinting at foreboding tension beneath their domestic life.