A big reason fans of the MCU keep coming back for these superhero adventures is because they like seeing a universe where everything is connected. Of course, with over twenty movies, a handful of television series, and plenty of more projects on the horizon, it can be hard keeping all the facts of this shared universe straight.
Inevitably, some inconsistencies have arisen over time with some established information later being contradicted. In some cases, the changes are given an attempted explanation that can often be messy, and sometimes it is never addressed at all. But these contradictions did not slip past MCU fans.
Gamora Didn't Know About Infinity Stones
The MacGuffin in Guardians of the Galaxy is an object called the Orb which is sought after by a number of people. Gamora was meant to retrieve the Orb for Thanos but instead joined the other heroes to sell it to The Collector.
However, The Collector explains that the Orb actually contains an Infinity Stone and they are all shocked by the power it possesses. However, Avengers: Infinity War proved that Gamora not only knew about the Infinity Stones beforehand, but she actually located the Soul Stone as well.
No One Person Can Hold An Infinity Stone
When The Collector explains the power of the Infinity Stones, he suggests that no single person and hold one. When his slave Carina attempts to, she is instantly killed and it nearly kills Ronan and Quill when they briefly hold it as well.
However, when Thanos goes in search of the Stones in Avengers: Infinity War, he is seen handling each of them without any trouble even before putting them in the gauntlet.
The Multiverse Is Fake
The multiverse has become a huge part of Phase 4 of the MCU. But fans might have forgotten that the first mention of it was back in Spider-Man: Far From Home. Mysterio claims to be a hero from the multiverse and Peter is blown away by the concept of that.
As it turns out, Mysterio was lying and he was just a disgruntled Stark Industries employee. So with the multiverse being part of some elaborate lie, it is strange that it was then proven to be a real thing that suddenly became an integral part of many of the MCU projects.
Gamora Is The Last Of Her Kind
The first Guardians of the Galaxy features the famous prison line-up scene that gives some background on the oddball heroes of the movie. When Gamora's file is shown on screen, it is revealed that she is the last survivor of the Zehoberei.
However, a flashback in Avengers: Infinity War shows that Gamora's people were selected by Thanos to test his "balancing" theory with half of them killed and half of them left alive. Thanos even confirms that the planet now flourishes
SHIELD And Hydra Are Gone
SHIELD was first introduced in Iron Man and quickly became an integral part of the MCU, even playing a big role in bringing the original Avengers together. That is why it was such a shock to see it fall in Captain America: The Winter Soldier when it is discovered SHIELD has been infiltrated by Hydra.
It seemed to be a game-changing moment for the MCU, but it ended up having very little effect. After briefly going into hiding, Nick Fury continues to operate in various movies as if SHIELD was never gone, and yet there is no explanation for this.
Tony Needs The Arc Reactor To Live
The arc reactor in the middle of Tony Stark's chest has been an iconic aspect of the character from the beginning and something. In the first Iron Man, the arc is used to keep shrapnel out of his heart, and he describes it as part of him and a "terrible privilege."
Oddly enough, this very important aspect of the character was retconned as being pretty unnecessary in Iron Man 3. At the end of the movie, Stark simply has an operation to remove the shrapnel suggesting he could have done that all along.
Odin Has The Infinity Gauntlet
The MCU movies are always packed with Easter eggs that fans spend endless time searching for. One of the most popular hidden secrets was in Thor when a brief glimpse inside Odin's vault reveals that the Infinity Gauntlet is there.
That tease was further confused when the post-credit scene of Avengers: Age of Ultron revealed that Thanos already had the gauntlet. This was eventually explained in Thor: Ragnarok when Hela reveals that Odin's gauntlet is a fake.
Vision's Creation
Seeing as Vision has an Infinity Stone lodged in his forehead, fans knew he was in trouble when Thanos came looking for the stones. In order to save him, the Avengers take him to Wakanda where Shuri questions the method banner used in bringing Vision to life to which Banner admits they hadn't considered that.
It is a nice moment that shows the genius Shuri is, but it completely rewrites the creation of Vision. First of all, it was Ultron who created him and Banner had nothing to do with it. Also, Ultron simply places the Mind Stone on the lifeless android so Shuri's questioning the science of the process makes less sense.
The Mandarin Is Made Up
One of the most controversial things in the MCU remains the Mandarin twist in Iron Man 3. Fans were excited to see Iron Man face-off with his archnemesis from the comics, but it turns out that the terrorist known as The Mandarin was actually just a drunk actor hired to play the role.
But in the Marvel One-Shot All the King, it is revealed that there really is a leader of the Ten Rings who did not take kindly to Trevor Slattery's portrayal of him. The character was then changed drastically from the comics in order to appear as the villain in Shang-Chi and the Legend of the Ten Rings.
There's Only One Way To Defeat Thanos
In Avengers: Infinity War, Doctor Strange uses the Time Stone to look at various alternate futures to see the outcome of their fight against Thanos. He sees that there is only one reality in which they are able to defeat the Mad Titan which is the one in which Tony Stark sacrifices himself.
However, Doctor Strange in the Multiverse of Madness finds the members of the Illuminati explaining that they also defeated Thanos in their universe when Strange used Dark Magic. It suggests that Tony's death might have been avoidable.