How Franklin Richards, the power cosmic and Doctor Doom's appearance in "The Fantastic Four: First Steps" credit scene affects "Avengers: Doomsday."

The Fantastic Four reveals why Galactus wants Franklin Richards and his true power might tie into Doctor Doom's endgame.

As Fantastic Four: First Steps heads towards its final act, the group is torn between two impossible choices: sacrifice all of Earth to Galactus, or Reed and Sue must give up their child Franklin, who contains the Power Cosmic and enough energy to satiate Galactus' hunger.