Great Earth is one of the many universes in the Marvel multiverse. Although similar in many ways to Earth 616, Great Earth has many differences and changes. When the Great Earth reality first emerged, various cosmic beings assumed it was a mirror world to Earth-616, and despite the various similarities, several things also play out differently whether it's someone's personality being different from another variant of themselves or events that occured on the world. After the emergence of Mutants, it would cause a year plus long debate on the future of society if they do or do not co-exist with Mutants.
In this reality, Spider-Man and the X-Men debut on the scene around the same time with the reception of them being not only very different but question-raising.
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