Earth-9916 is an alternate reality where the Vision did not marry Scarlet Witch.
History[]
In this reality, Wonder Man ends up marrying Scarlet Witch, instead of Vision. Spider-Man was among the heroes that attended the wedding.
However, Ultron transferred his mind into Vision, and used Vision's body to kill Wonder Man. Wonder Man then transferred his own mind into Vision's body and overrode Ultron's mind.