The darkest villainy would have been to sentence two universes full of trillions and trillions of individuals to death, like they were willing to do today.
Also the precedents of heroes being murderers ? Mass murderers at that ? In a Marvel title ? Really ?
That's a story arc I would be interested in reading actually. Maybe an alternate version of Peter Quill or Richard Rider makes the jump to 616 in a quest for answers, if not retribution...
Heh, why not.