Appearing in "Days of Future Smash, Part 4: The Hydra Years"
- Captain America (Steve Rogers) (First appearance chronologically)
- Old Captain America (Steve Rogers)
- Alternate Hydra
Synopsis for "Days of Future Smash, Part 4: The Hydra Years"
Chasing Leader through time to World War II, Hulk teams up with Captain America to stop Red Skull. In the present, the Agents of S.M.A.S.H. fight to free the world from Hydra.
- Red Hulk's quote "Sweet Betsy Ross", could either be a reference to his aunt Golden Girl in the comics or the real life person who knitted the American flag.
- This episode's title is a reference to Days of Future Past storyline.