Warning: Contains SPOILERS for MCU Phase 4 movies and TV shows

2021 has been a big year for the MCU - but Marvel's movies and Disney+ TV shows have also highlighted some massive MCU plot holes. The Marvel Cinematic Universe is one of Hollywood's greatest successes - a complex shared universe of films and TV shows that somehow weave together into a grand overarching narrative. Marvel's Phase 4 was delayed due to the coronavirus pandemic, but finally kicked off in spectacular fashion in 2021. However, even with all the excitement, there were still some oversights.

It's been a big year for the MCU, with the multiverse officially introduced in Loki - and playing a major role in Spider-Man: No Way Home, when a misfiring spell by Doctor Strange brought heroes and villains from other dimensions into the main Marvel timeline. Wanda Maximoff became the Scarlet Witch, apparently a being with the power to destroy the entire planet, while Earth barely survived the Emergence of the Celestial Tiamut. Meanwhile, on a smaller scale, Sam Wilson became the new Captain America and Hawkeye gained a new sidekick. Phase 4 is proving to be just as exciting and explosive as the first three phases.

Related: After 13 Years, The MCU Officially Has "Supervillains"

But even Marvel get things wrong sometimes. The first year of Phase 4 has featured a number of striking plot holes, with some of the most disturbing emerging precisely because Marvel had so many projects in the works at once. Here are all the worst MCU plot holes from 2021.

Why Didn't The Masters Of The Mystic Arts Turn Up In WandaVision?

WandaVision Scarlet Witch Elizabeth Olsen

2021 opened with WandaVision, one of the highlights of the year for Marvel Studios. But even this show wasn't without plot holes, the most notable being the fact none of the Masters of the Mystic Arts came to check out what was going on in Westview. The Masters of the Mystic Arts are supposed to protect the world from magical threats, and yet they appear to have been blissfully unaware of Wanda Maximoff's flare of Chaos Magic - a power apparently great enough to potentially destroy the entire planet. Wong may have taken over as Sorcerer Supreme after the Ancient One's death, but WandaVision suggests he hasn't been doing a good job of keeping the Earth safe.

Just How Does The Multiverse Work?

Nexus in Loki

Loki served to explain the basic principles of the MCU's multiverse, with its particular focus on the idea of nexus points - moments where a branched timeline can be created. Unfortunately Marvel produced most of 2021's multiversal releases at the same time, and they didn't hold a creative summit deciding the rules of said multiverse until after they'd finished them. This led to a number of frustrating contradictions, not least between Loki and the animated series Marvel's What If...?. That show introduced a completely different idea, described as an "absolute point in time," which contrasted markedly with the nexus points - but which What If...?'s showrunners were convinced was really the same thing.

How Much Does The World Know About Avengers: Endgame?

The Avengers charge into battle in Avengers: Endgame

One lingering question running through all of 2021 has been exactly how much the world knows about the events of Avengers: Endgame. Jimmy Woo and Darcy Lewis acted as audience surrogates in WandaVision, and thus were as familiar with everything that happened as any viewer who's watched that particular blockbuster a dozen times. But at other times, characters have seemed to have next to no knowledge of how things played out; the perfect example is Yelena Belova, who even believed Hawkeye was responsible for Black Widow's death. In general, it looks as though the Avengers have revealed everything but the time travel mission - which raises the question of what the world thinks happened to the Infinity Stones, and why they don't have a body for Steve Rogers' Captain America, who they presumably believe died in battle with Thanos.

Related: MCU's Multiverse & Alternate Timeline Rules Explained (Based On Loki & Endgame)

How Recognizable Are The Avengers?

Bucky and Sam smiling in the FatWS finale

A related MCU plot hole is the question of how recognizable the Avengers are now. The issue first came up in The Falcon & the Winter Soldier, with the two leads instantly identified by passers-by in some scenes - and yet Bucky was able to travel the world befriending people in an attempt to redeem himself, without anyone recognizing him. The problem was even more acute in Hawkeye, with Clint Barton unable to have a meal with his family without being thanked for saving the world - and yet only spotted in the street when the plot demanded.

Why Does Red Guardian Think He Fought Captain America?

Captain America Red Guardian

Black Widow confirmed the Cold War was a superhero arms race in the MCU, with the Soviet Union creating at least one super-soldier of their own - Red Guardian. Alexei claimed he'd gone head-to-head with Captain America at one point, but the timeline doesn't match up at all; Steve Rogers was still on ice during the Cold War, only discovered roughly 20 years after the Soviet Union had collapsed. The most likely explanation is that the U.S. government had another Captain America in the field during the 1980s, whose tale has yet to be told.

Why Didn't The Masters Of The Mystic Arts Confront The Ten Rings?

Wenwu with the Ten Rings in Shang-Chi.

Shang-Chi & the Legend of the Ten Rings is another one of Marvel's stronger releases in 2021, but even this isn't perfect - and some of the biggest problems come from the shared universe. The most puzzling problem is the fact that Wenwu has possessed the ancient artifacts known as the Ten Rings for centuries, wreaking havoc across the entire world, and yet the Masters of the Mystic Arts have never crossed his path before now. All in all, Phase 4 really does seem to imply the Masters have been asleep on the job for quite some time.

Why Didn't Wenwu Just Fly Over The Maze?

Shang-Chi Ta-Lo

Wenwu has learned the secret location of Ta-Lo, a mystical realm that can only be accessed by traveling through a dangerously fluid forest. Shang-Chi and his friends manage to navigate the forest with the help of Maurice, but Wenwu has to wait for one window each year when the path is briefly safe. It's a classic concept from mythology, but unfortunately it really doesn't work in a modern context - because Wenwu could simply fly over the forest in a helicopter. This one's rather problematic, and it can only be explained by assuming the magic somehow prevents anyone doing that.

Related: Shang-Chi Secretly Hinted At A Korean Avenger

How Was The Dweller In Darkness Manipulating Wenwu?

Shang Chi Concept Art of final battle with Dweller in Darkness by Andy Park CROPPED

The Dweller In Darkness is, unfortunately, another major plot hole in Shang-Chi & the Legend of the Ten Rings. It seems the Dweller In Darkness found its way to Ta-Lo millennia ago, laying waste to that world before it was trapped - sealed away in an enchanted mountain. But somehow the Dweller In Darkness has still been able to reach across the dimensions, attempting to tempt those it believed powerful enough to free it from its imprisonment. It's unclear exactly how the Dweller In Darkness was able to do this, and it's also odd the creature only seems to have chosen the Mandarin in recent years - raising the question of why it didn't try to tempt Tony Stark or Thor, for example.

Why Are Eternals' Celestials So Different To Everything Seen In The MCU To Date?

A close up image of Arishem the Celestial in Eternals

Eternals finally introduced the MCU's cosmic space gods, the Celestials - and in doing so, it contradicted everything the MCU had established about them before now. The Guardians of the Galaxy films had suggested the Celestials were now extinct, and it had given a glimpse of an ancient Celestial wielding the Power Stone to judge an entire world - but suffice to say that particular Celestial was small fry compared to even the newborn Tiamut. Guardians of the Galaxy Vol. 2 had introduced Ego, who claimed to be the last Celestial, and yet his powers worked completely differently to Arishem and Tiamut's. Eternals even contradicted Avengers: Endgame, which had suggested Vormir - the hiding place of the Soul Stone - had been the center of Celestial civilization. Marvel's clearly carried out something of a course correction when it comes to the Celestials, and it's a little jarring.

How Did The Earth Survive The Beginning Of Tiamut's Emergence?

Tiamut in Eternals

The Eternals learn a Celestial seed lies at the heart of the Earth - Tiamut, who begins to emerge. The complete Emergence would apparently destroy the entire planet, but it's impossible to understand how the partial Emergence seen in Eternals doesn't render the Earth uninhabitable anyway. Tiamut has literally torn his way out of the planet's core, disrupting the mantle and breaking through to the surface. The breach of the crust alone should have triggered an extinction-level event, yet the planet appears to survive.

Has Hawkeye Actually Retired Or Not?

Hawkeye-Clint-Pym-Arrow

Clint Barton retired in the aftermath of Avengers: Age of Ultron - or, at least, he tried to. All the evidence of Hawkeye appears to suggest he's still trying to bow out of the superhero scene - with the exception of one scene. While he could understandably have a stash of Stark tech arrows, there's no sensible point in the timeline when Hawkeye could have acquired Pym particles. The problem is even more pronounced given those particular arrows bore the brand of Pym-Tech; Hank Pym never handed over the secret of Pym particles to his old company. These weapons only work if Pym has returned to Pym-Tech, and given Hawkeye some new trick arrows - but there's no reason a retired Avenger should want them. The Pym arrows may be cool, but they don't make any sense.

Related: Hawkeye's Pym Arrow Hints Hank Pym Is The MCU's New Tony Stark

How Exactly Do The Spells In Spider-Man: No Way Home Work?

Doctor Strange casts a memory spell in Spider-Man: No Way Home.

Doctor Strange claimed to be performing memory spells in Spider-Man: No Way Home, but in truth they wouldn't solve Peter Parker's identity problems. It wouldn't matter if the world forgot Peter Parker was Spider-Man; the moment somebody did a Google search for Spider-Man, they'd stumble upon an old newspaper article. Flash Thompson would certainly wonder what was going on with his bank balance, while J. Jonah Jameson would notice Spider-Man articles he'd forgotten when he checked the Daily Bugle's site analytics. Doctor Strange may have told Spider-Man he was working magic with people's memories, but in truth he was rewriting reality on the fly - which explains why the spell backfired so badly. But even the backfire was poorly described, with Strange apparently wrong when he suggested only people who knew Peter Parker's secret identity in another universe were brought through - and also wrong when he said all the villains were destined to die, because neither Sandman nor Lizard did in their own timelines.

How Did Spider-Man's Webbing Last So Long?

Doctor Strange on a train in Spider Man No Way Home

In one of the coolest scenes in Spider-Man: No Way Home, Peter Parker successfully outsmarted Doctor Strange in the Mirror Dimension - taking advantage of its geometry to spin a web that captured the Master of the Mystic Arts. It was a smart strategy, with Doctor Strange trapped hanging over the Grand Canyon for 12 hours. The only problem is that, in both the comics and the MCU, Spider-Man's webbing has been designed to dissolve after a certain time-period. In Spider-Man: Homecoming, the wall-crawler told Aaron Davis it would dissolve after two hours - so Doctor Strange really shouldn't have been trapped for six times that length of time.

More: Did Marvel's Disney+ Change In 2021 Actually Work?

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