Majin Démigra or Merged Zamasu?

[Steven Bloodriver]

Which one out of these two would be the perfect challenge?

[Doctor.]

Perfect challenge for who? In what way?

[Steven Bloodriver]

Perfect challenge for who? In what way?

1) For a member of the Z Fighters or one of their greatest of enemies, like Mr. Son Goku during the Universe Survival Saga or even Sandubadear respectively for example.

2) As a sort of secret final boss, like either having the God of the Dark Demon Realm or the Destroyer of the Future appear just when the likes of Golden Frieza is defeated.