The MCU has introduced several different ways to travel through the multiverse and its many dimensions. Throughout Phase 4, the scope of the MCU's multiverse has grown at an incredible rate, presenting various alternate realities filled with different versions of familiar faces and even brand-new characters that don't exist in the main MCU universe. But while the multiverse has taken a central spot in the franchise, there are still more questions than answers regarding its nature.
Like superpowers, deities, and sorcery, the multiverse can be approached through both scientific and magical means. Scientists like Hank Pym and magic users such as Doctor Strange and Scarlet Witch have made important discoveries about the multiverse, but not even they have a strong grasp of its inner workings. It seems that the multiverse is quickly becoming a big threat, and every time a character begins to understand it, another multiversal event arrives to shake things up.
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The MCU has introduced universes like the Avengers' Earth-616, the Illuminati's Earth-838, and the Raimi universe. It also has featured dimensions such as the Soul World, the Ancestral Plane, and Ta-Lo. While these dimensions aren't exactly parallel universes, they're still extraneous realities that can't be accessed through regular means of space travel. Concepts like incursions and variants are yet to be fully explained, but if there's something certain, it's that there's more than one way to travel to other planes of reality. These are the ones introduced in the MCU so far.
A dimension in and of itself, the Quantum Realm is so small that it is nearly impossible to even detect. Avengers:
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