The simplest explanation is not always the most fun. Yes, you could say a school of mutants has always existed in West Chester, NY, but chose not to engage in any of the world threatening struggles– boring, (and also, very unlike the X-Men to ignore such threats). And the Baxter Building has been in the Microverse the whole time? –not buying it.
Captain Marvel by Artgem (aka Stanley Lau)
You could solve it easily with time travel, via the Infinity Gauntlet, with Captain Marvel resetting the entire universe, but one of things is not like the others– enter the XMen in an end credit trailer to the deafening screams of Marvel fans (I would be one of them), as Stan Lee begins reading a copy of the Daily Bugle with Fantastic Four on the front page. This is certainly scifi plausible and would be acceptable, but I have another theory..
..during the final battle with Thanos, Scarlet Witch alters reality with her magic, destroying the Infinity Stones, ceasing Thanos to have ever existed, but also inadvertently alters the reality of the universe. The previously vaporized superheroes return and BOOM the XMen now exist, and have always existed according to everyone, except Wanda. Wolverine, Rogue and SpiderWoman (Jessica Drew) are standing beside their teammates, the Avengers, The Fantastic Four can be seen far away atop the Baxter Building, and far, far away, the Silver Surfer makes a deal with Galactus to save Zenn-la.
The new Wonder Woman comic book series, titled, ‘The Legend of Wonder Woman‘ will debut digitally online in January 2016, and will be written and drawn by a woman, Renae De LIz (ink/colorist by Ray Dillon). this new 9 issue comic book series will tell the story of a young Diana, before she leaves Themyscira, the island of immortal Amazon warriors, to venture out into Man’s World, on a path of Justice. it is unclear if ‘The Legend of Wonder Woman’ will be a re-imagined reboot or just an untold story fitting into pre-existing DC Comics canon, or if the birth of Diana will be re-explained. the original story of the birth of Diana, Wonder Woman, was her mother, Hippolyta wanted a child so desperately that she sculpted a child out of clay. the goddesses took pity on Hippolyta and granted the clay child life. the re-imagined version, and current version, is that the previous, was just a cover story to conceal a dark side of the Amazons and that Zeus was Diana’s father. the dark side was that the Amazons would get busy with shipwrecked sailors, raise their daughters as amazons and their sons would become slaves. I much prefer the original version as it seems to fit fluidly within actual Greek myths. This new Wonder Woman story is said to be amazing with fantastic artwork, looking forward to it. it is also unclear if ‘The Legend of Wonder Woman’ will tie into the upcoming DC Cinematic Universe film, ‘Batman v Superman: The Dawn of Justice,’ (premiering March 25, 2016) or the solo ‘Wonder Woman’ movie starring Gal Gadot.