- Magneto (Erik Magnus Lehnsherr) (First appearance)
- The Man / Reptil (Humberto Lopez) (First appearance)
- Scarlet Empress (Wanda Maximoff) (First appearance) (Main story and flashback)
- Sentinels (First appearance) (Main story and flashback)
- Dark Surfer (Norrin Radd) (Mentioned)
- Squirrel Girl (Mentioned)
- Reptil (Humberto Lopez) (Cameo)
- Luke Cage (Cameo)
- Hawkeye (Cameo)
Races and Species:
- Earth-TRN172 (First appearance)
After being thrown into a portal by Dark Surfer, Falcon and H.E.R.B.I.E. find themselves in an alternate reality where Scarlet Witch is an evil empress who rules the world. With help from an elderly Magneto and a strong Reptil, Falcon and H.E.R.B.I.E. must try to convince Scarlet Witch that she is good and let the world be in peace.
- Title card's issue homage X-Men #141
- The title and several aspects of the episode are a reference to the X-Men's Days of Future Past story line.
- One of the terms H.E.R.B.I.E. uses to refer to the alternate world is a What If?