While the Marvel Cinematic Universe may be one of the most popular and profitable film franchises on the planet, it's not perfect. When weaving such a large and expansive universe, it's a given that there will be some slip-ups along the way, especially when it comes to continuity, causing inevitable plot holes. While some, like the infamous Spider-Man: Homecoming plothole, are more popular than others, some have slipped under the radar as well.

Whether they're known by the general public or not fully acknowledged, the plot holes make things a bit more confusing in the MCU, especially for viewers looking back on how things have played out over the years. They're nowhere near severe enough to ruin an experience, but a few are puzzling enough to get people scratching their heads and second-guessing what they've seen.

10 The 8 Years Later Conundrum

'Spider-Man: Homecoming' (2017)

One of the more popular plot holes in the Marvel Cinematic Universe comes at the very beginning of Spider-Man: Homecoming. It was previously established that the Battle of New York in The Avengers took place in 2012, so when the film opens in the aftermath of the Battle of New York before flashing forward eight years into the future, there's a small slip-up that convolutes the timeline of the universe.

See, No Way Home is supposedly set in 2017, but the title card "8 years later" implies The Avengers actually took place in 2008, which is impossible. The MCU supposedly takes place chronologically, give or take one or two movies set entirely in the past. However, the main MCU timeline was supposed to happen in the year it was released, making this one of the franchise's most egregious plot holes.

9 Electro Knows Spider-Man's Identity

'Spider-Man: No Way Home' (2021)

The reveal at the beginning of Spider-Man: No Way Home that the multiversal villains coming to the Marvel Cinematic Universe know who Spider-Man is under the mask causes questions to arise regarding Electro's (Jamie Foxx) involvement. In his original appearance in The Amazing Spider-Man 2, it's never established that Electro knows who Spider-Man really is, and he never finds out.

Some have decided through head-canon that he is actually a variant and not necessarily the exact version from The Amazing Spider-Man 2. Another theory suggests that he found out when he became pure electricity somehow at the end of The Amazing Spider-Man 2's final battle. But the fact of the matter is, it's never established in the film, so there's no real explanation as to how he's there.

8 Gamora is the Last of Her Race

'Avengers: Infinity War' (2018)

After the Guardians are first arrested in their debut film, Guardians of the Galaxy, it's established that Gamora (Zoe Saldaña) is the last remaining survivor of her race. But when Avengers: Infinity War came around and decided to show the origin of Thanos (Josh Brolin) and Gamora's father-adoptive-daughter relationship, it was shown that only half of her race was massacred. Thanos also says that her planet and people are thriving, living better than they ever had.

If her planet and people were thriving and doing so well, it doesn't make much sense that people have been led to believe that they were all murdered. The Mad Titan wouldn't have covered it up since he's so proud of his mission. Thus, it doesn't make much sense that the general populous thinks that Gamora is the last of her civilization, and it's even weirder that she doesn't correct them.

7 S.H.I.E.L.D. Wasn't Called S.H.I.E.L.D. Until 2008

'Iron Man' (2008)

In Iron Man, it's established by Agent Phil Coulson (Clark Gregg) that S.H.I.E.L.D. had yet to call themselves by the acronym and only been called by its full name, Strategic Homeland Intervention, Enforcement, and Logistics Division. A decade later, Captain Marvel shows them calling themselves S.H.I.E.L.D. since 1995.

It doesn't make sense that Coulson would deliberately call the organization by its long-winded true name rather than its acronym until 2008 and claim that they had never called themselves that. In fact, the reveal makes the fan-favorite Coulson look a bit weird and not as knowledgeable as he was sold to be. It's nothing wild, but enough to have heads scratching.

6 Avengers Tower Stopped Appearing

'Hawkeye' (2021)

Starting with Hawkeye and continuing to this day, the ex-Avengers Tower stopped appearing in New York and was replaced with the real-world building in that location, the MetLife Building. Apparently, the building had been sold by a mystery party, but the was no follow-through.

The sale of the once-Avengers Tower established in Spider-Man: Homecoming was a really big deal, causing fans to continuously speculate who bought the building. Some thought it would be the Marvel Cinematic Universe version of Oscorp or the Baxter Foundation, which were honestly not ridiculous assumptions. It's not like the building was never significant; thus, it's odd that such an important building seems to have been forgotten. Who knows? Maybe MetLife actually bought it.

5 Aldrich Killian Made Up the Mandarin Name

'Iron Man 3' (2013)

In the Marvel One-Shot All Hail the King, it was firmly established that the Mandarin mantle actually existed outside of Aldrich Killian (Guy Pearce), as he merely took it for his operation. It was a massive deal for the Marvel fanbase because it confirmed that the real Mandarin could be coming in the future.

But, when the real mantle-holder, Xu Wenwu (Tony Leung Chiu-wai), appeared in Shang-Chi and the Legend of the Ten Rings, he concretely claimed that Aldrich Killian actually made up the name. Why would he claim that if the name previously existed? Who came up with the Mandarin title and why? No one is really sure. It's such a puzzling choice, too, as The Mandarin is among Marvel's most iconic villains, so seeing the MCU treat him with such little care is questionable.

4 The Loss of Mark XLII's Power

'Iron Man 3' (2013)

It's a crucial plot point in Iron Man 3 when Tony Stark's (Robert Downey Jr.) armor loses power over Tennessee, leaving him stranded. However, it seems the filmmakers forgot one crucial plot point that has been unwaveringly established in the past: the arc reactor in Tony's chest can power the Iron Man armor. So, why on Earth does he hook the Mark XLII to a car battery?

Yes, if he loses power in the arc reactor, he will die. But if there's an arc reactor that can power all of Stark Tower, a little bit of juice from Tony's reactor would certainly have the power to give the Mark XLII a jump-start. The Tennessee plot is quite engaging and shows a new side to Tony, but it's somewhat unnecessary, especially considering everything that was established by Iron Man's first three movies.

3 Fury Claimed Thor Was the First Alien On Earth

'The Avengers' (2012)

In The Avengers, when Nick Fury (Samuel L. Jackson) is defending weaponizing the Tesseract, he claims that it's because of Thor (Chris Hemsworth), as he was the first outer-space visitor to land on the planet. However, this claim was disproved when Captain Marvel was released in 2019, as Captain Marvel (Brie Larson) comes to Earth, and Fury interacts with her and numerous other aliens, like the Kree and the Skrulls.

So, if Fury and S.H.I.E.L.D. were truly spooked by alien life being real, why wouldn't they begin developing anti-alien weapons of any kind (even without the Tesseract) when he met Captain Marvel seventeen years earlier in 1995? Captain Marvel, the Kree and the Skrulls are just as powerful and potentially dangerous as Asgardians, so it's not like their appearance is not significant.

2 Captain America Couldn't Bring the Stones Back

'Avengers: Endgame' (2019)

At the end of Avengers: Endgame, the Avengers must bring the Infinity Stones back to where they came from after stealing them from the past. After all, Bruce Banner (Mark Ruffalo) promised the Ancient One (Tilda Swinton) that they would. Alas, there's a slight issue with doing so. The Marvel Cinematic Universe had the tendency to introduce Infinity Stones as other items and forms before they became the stones themselves.

For example, the Space Stone was the Tesseract, and the Power Stone was the Orb before they became stones. However, their original nature is never fully explained, so it's quite impossible for Captain America (Chris Evans) to have returned the stones to their original forms; how did he liquify the Reality Stone to get her back into Jane Foster's (Natalie Portman) body? No one has a clue.

1 Sling Rings Can Travel the Multiverse

'Doctor Strange' (2016)

Many forget that in Doctor Strange, it's established that the Sling Rings Doctor Strange (Benedict Cumberbatch) uses all times can traverse the multiverse. So, when Doctor Strange in the Multiverse of Madness reveals that Scarlet Witch's (Elizabeth Olsen) means to take America Chavez's (Xochitl Gomez) powers so she can travel through the multiverse, it made no sense for fans who remembered what the Sling Rings can do.

The Sling Rings being able to travel the multiverse was something that was brought up and never talked about again. The ability to go through the multiverse would have been incredibly helpful throughout the Marvel Cinematic Universe and completely erased Scarlet Witch's need to kill America for her powers. The entire plot of the second Doctor Strange and Scarlet Witch's descent into madness could have been completely erased if everyone just remembered that the Sling Rings could do exactly what she needed.

NEXT: The 10 Most Powerful MCU Characters Introduced After 'Avengers: Endgame', Ranked