An extended clip from Spider-Man: Far From Home reveals that the MCU is Earth-616. Marvel's been setting up the multiverse for quite some time, with a number of references in the Thor films. But it's become a lot more explicit of late, with Avengers: Endgame using the concept of time travel to create a host of alternate realities.

The Spider-Man: Far From Home trailer revealed that Mysterio claims to have come from another dimension. According to Nick Fury, the events of Avengers: Endgame - including multiple snaps, the destruction of the Infinity Stones, and a whole lot of time travel - have torn a hole in the fabric of the space-time continuum. Mysterio claims to have come from another dimension - and presumably the Elemental creatures wreaking havoc across Europe are also from another reality. The jury's out as to whether or not Mysterio is telling the truth, of course; in the comics, the sorcerer pretended to be a superhero on his first appearance. Assuming he is, though, the multiverse opens up a whole host of new opportunities for the MCU.