The The Avengers; if that film had failed, the MCU would have collapsed like a house of cards.
But Marvel's gamble paid off, Guardians of the Galaxy. And yet, for all that's the case, for Phase 4 the MCU has become something even better.
The MCU has changed form in both form and narrative, so much so that "Marvel Cinematic Universe" - a powerful brand that will no doubt never be retired by Marvel - is no longer an accurate name for it. In of form, the Ant-Man & the Wasp: Quantumania. This is true transmedia, true connectivity.
But the MCU's transformation is even better than that because no longer is Marvel dealing with one shared universe - it's now exploring an entire Multiverse. The wealth of storytelling opportunities created by the Multiverse was made clear in Loki, which featured everything from a female version of the trickster god (the delightful Sylvie, played by Sophia Di Martino) to an alligator who fans have taken to calling Croki. Marvel Zombies plot, a timeline in which the Winter Soldier goes up against a zombie Captain America.
All this means the MCU has evolved completely. No longer can it accurately be described as a shared cinematic universe: now it is a shared transmedia Multiverse. Marvel is unlikely to retire the MCU brand, simply because it's too valuable, but this should really now be called the Marvel Transmedia Multiverse.
