The "Doomsday" plot leak also seems to confirm the big fight at the X-Men mansion in the universe where Monica Rambeau ended up at the end of "The Marvels." That universe's anchor being is a Professor X (Patrick Stewart) variant that Doom wants to kill. Interestingly, Earth-616 and Earth-10005 -- where Monica is -- are on a collision course.

This story discusses major plot developments, including the ending and post-credits scenes, in "The Fantastic Four: First Steps," currently playing in theaters. From the very first scene, the question of what will become of the child of Reed Richards (Pedro Pascal) and Sue Storm (Vanessa Kirby) looms over "The Fantastic Four: First Steps.

A good chunk of Doomsday could focus on a clash between Avengers and X-Men with RDJ’s Doom cackling in the background, with a kidnapped Franklin by his side. The premise certainly gives the Fantastic Four a reason to breach their multiversal walls and zip over to 616 to meet the New Avengers.