How Across The Spider-Verse Changes Marvel's Earth-1610 (For Better Or Worse)
While there are plenty of Easter eggs you may have missed in "Spider-Man: Across the Spider-Verse," the movie revealed that Miles Morales' (Shameik Moore) universe is the on-screen version of Earth-1610. Unlike the "Doctor Strange" sequel confirming the Marvel Cinematic Universe is Earth-616, comic book fans won't be upset that "Across the Spider-Verse" brings another version of Earth-1610 to life, and that's because it's not the best thing to come from Marvel Comics.
Earth-1610 (aka the Ultimate Universe) debuted with "Ultimate Spider-Man" and "Ultimate X-Men" in the early 2000s, reimagining iconic characters throughout the Marvel Universe. For the most part, Earth-1610 closely resembles Earth-616, with practically every Marvel character having an alternate-universe counterpart, unlike Sony's "Spider-Verse," which just has Miles. Earth-1610 even has its own version of the Avengers, aptly named The Ultimates.
However, many of these characters are drastically different interpretations than the ones we know and love. Captain America regularly uses guns and kills people. Hulk fully accepts his monster persona and eats people. Black Widow kills Hawkeye's entire family. Most of those stories were unnecessarily violent, so it's probably best that Sony's "Spider-Verse" is drastically different and only has Miles.
Ultimatum was the Ultimate Universe's breaking point
The Ultimate Universe wasn't always bad. Not only did it give us Miles Morales, but "Ultimate Spider-Man" is a fan-favorite depiction of Peter Parker and his origin story. However, the universe's biggest storyline, "Ultimatum," proved it was for the best that Marvel destroyed Earth-1610 in "Secret Wars."
"Ultimatum" continued the Ultimate Universe's overly-violent trend, as Magneto seeks revenge against the entire world for the deaths of his children. He kills millions of people worldwide by manipulating Earth's magnetic fields, causing massive tidal waves to hit Manhattan and Latveria to freeze over. When Professor X confronts him, Magento snaps his neck. While Magneto has always walked a line between hero and villain, he doesn't kill without reason and certainly wouldn't murder his long-time friend Charles Xavier.
Plenty more makes "Ultimatum" an infamous comic run, with countless characters dying in the event, many of those being off-screen deaths. Spider-Man finds Daredevil dead, numerous characters drown in the wave ravaging New York, and that's just the beginning. Some of the story's most gruesome deaths include Blob eating the Wasp, Hank Pym biting off Blob's head, The Thing crushing Dr. Doom's head, and Magneto ripping out Wolverine's skeleton. We aren't sure why the Ultimate Universe had such a fixation with decapitations or its general sense of over-the-top violence, but no one's missing stories set on Earth-1610.