Avengers: Endgame might have set up the villain for Marvel's Phase 4, with its time-travel plot paving the way for Kang the Conqueror to be the antagonist of Avengers 5. With Thanos and the Infinity Stones over with, the MCU is in need of a new Big Bad for whatever form the next Avengers movie takes, and Kang would fit the bill nicely.
There's been a lot of talk about how Marvel will replace Thanos, who proved a major hit as a villain, especially in Avengers: Infinity War, with lots of talk about characters such as Galactus, Annihilus, or even Norman Osborn. There's no shortage of villain options for the MCU, but since they like to tease things before they happen, it's worth looking back at Avengers: Endgame and what it might be setting up.
Thanks to its use of time-travel, one of the biggest hints is to Kang the Conqueror, a villain who is all about traveling through time, and would be a big enough threat to take on the Avengers. Although his rights were with Fox, the Disney takeover means he's very much in play, and there's a chance he's already shaping into the villain of MCU Phase 4 and Avengers 5.
Kang The Conqueror Explained
In Kang the Conqueror's first Marvel Comics appearance, he wasn't called Kang at all. Debuting in Fantastic Four #19, he went by the name Rama-Tut. Real name Nathaniel Richards (he might be a descendant of Reed Richards), he traveled back in time to Ancient Egypt, becoming the Pharoh and taking the future-Apocalypse as his heir. It wasn't until The Avengers #8 a year later that Kang the Conqueror would formally appear, fighting an Avengers line-up that included Thor, Wasp, and Spider-Man (all heroes who'll be present in the MCU's Phase 4), but then having various identities is kind of Kang's thing.
Other iterations of the character include Immortus, a future version of Kang who resides in Limbo, and Iron Lad, who was an original part of the Young Avengers team. There's also Victor Timely, the mayor of a small town Kang established as a place to go for some down time. The reason for having multiple alter-egos is that Kang the Conqueror is a time-traveler, and alongside these versions are multiple duplicates of Kang, with each journey through time creating a new one.
Although Richards doesn't actually possess any typical superpowers, he is a genius who specializes in time-travel, and possesses a time-ship that allows him to visit any century, through which he's able to collect an array of different weapons and armors to give himself enhanced abilities, utilizing incredibly advanced technology that no one else has access to or can match. He's also able to recruit different armies, which leads to him conquering different time periods, and further enables him to go toe-to-toe with superheroes. That, combined with his ability to time-travel better than anyone else, makes him a compelling choice for The Avengers 5.
Avengers: Endgame Created The Multiverse (In Multiple Ways)
Avengers: Endgame fully introduced time-travel to the MCU. Although this had already been shown with Doctor Strange and the Time Stone, it took on a much greater importance here, and by utilizing the Quantum Realm it established a means of time-travel existing without the use of an Infinity Stone (which is handy given they've been destroyed). However, along with establishing this new form of time-travel, it also meant creating multiple timelines.
As the Ancient One explained in Avengers: Endgame, every time the Avengers take an Infinity Stone from its place in the timeline, a new branch reality is created. In theory, these are closed by Captain America returning the Stones back to their correct place in time, but it's not quite so simple. We see Loki take the Tesseract and disappear, while Cap decides to stay in the past of another reality (if you listen to the Russos' explanation, at least), which leaves two of these branches very much in play. Add in the Thanos from 2014 making the leap to the present of 2023, and there are potentially three (and maybe even more) timelines created in Avengers: Endgame that still exist in the MCU.
That's on top of the different dimensions that were already established by Doctor Strange (the Dark Dimension) and Ant-Man (the Quantum Realm), meaning that despite how Spider-Man: Far From Home treats it, the multiverse does indeed exist in the MCU, which means there's scope for a villain like Kang the Conqueror to exploit that and emerge in Avengers 5.
How Kang Could Fit Into MCU Phase 4
With time-travel and multiple timelines now firmly established within the MCU, then the chances of Kang the Conqueror appearing in Phase 4 are greatly increased, because both of those elements allow for him to turn up at just about any point. Following on from Thanos and the Infinity Stones, then it's unlikely Marvel will be setting up their next villain in such a direct, all-encompassing way, but since they already have everything needed to introduce Kang then he makes perfect sense as the next antagonist.
Phase 4 will be switching between expanding the cosmic arm of the MCU (The Eternals, Guardians of the Galaxy 3, Doctor Strange 2) and telling smaller, more street-level stories (Black Widow, Shang-Chi, Spider-Man 3). In Kang the Conqueror, Marvel would be getting themselves a villain who can do both: as a time-traveler, he fits in with the former, but since he's also an Earth-origin character without real superpowers, he doesn't feel too big for the latter.
The Eternals is a cosmic MCU prequel, so there's a chance of them further developing ideas around time-travel and different dimensions, and likewise Doctor Strange 2. Loki, the Disney+ TV series, is another way Phase 4 can indirectly tease Kang. Looking at the planned Disney+ MCU series, they all have some sense of purpose: Falcon & Winter Soldier is about establishing the new Captain America; Hawkeye will be setting up Young Avengers. Loki is oddly separate from that because he's just off on his own, but Kevin Feige has promised these shows will have an impact on the MCU. Since Loki will be in a different timeline, then by using that as one of the building blocks of Kang gives it a place in the grander scheme of things. It's also worth noting that Kang has connections to the Fantastic Four, and with the Fox deal being completed things have fallen nicely into place for him to appear, although Marvel's First Family showing up in the MCU still feels like it's a long way off.
It's unclear as yet just how the Avengers will be shaping up in Phase 4, but Avengers 5 will happen at some point. It'll need to pull together a group of different heroes and disparate strands, and Kang being the villain can link Phase 4 and Avengers 5 all the way back to Avengers: Endgame, which is the kind of storytelling and world-building Marvel love to do. If he turns up in Avengers 5, then it connects things together, and most importantly gives the Avengers an all-new threat to face who'd be different to Thanos, but still worthy of the team-up.