For the longest time, Earth-616 was to Marvel as Earth-1 is the DC. It's the prime earth where the main continuity of the multiverse takes place.
However, the events of the most recent Secret Wars (2015) caused all of the separate worlds in the Marvel multiverse to merge into one singular universe, thus taking away the need to classify different worlds.
Now that there's just been one world within the Marvel comicsverse, the crew at the House of Ideas needed a new place to use the 616. They've now found out how to use the number within the pages of Brian Michael Bendis' Invincible Iron Man #8 released this week.
As Ironheart, Nick Fury, and crew gathered at a terrorist attack at the Smithsonian, a villain attacked the scene, leaving Fury to declare it as a 616.
"This is Nick Fury with S.H.I.E.L.D. Command at the Smithsonian," the S.H.I.E.L.D. leader said as he looked on towards the destruction. "We have a 616, meta-human attack at the bombing location."
He added that a full battalion of Hulkbusters was needed on location, in addition to placing the entire city of lockdown until further notice.
You heard that right, Marvel fans. Now within Marvel canon, 616 is now the codename for what seems to be an attack that takes place immediately after a terrorist attack that happened in the same location.
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