The Marvel Cinematic Universe has been an impressive hit among comic fans for over a decade. We mention “impressive” because the MCU must walk a fine line: they must adapt these characters and stories in a way that is both familiar to fans and accessible to casual moviegoers. Along the way, they have had to make some fairly major changes. Sometimes, entire characters are swapped out and given different roles. Other times, a familiar character may be utterly unrecognizable by the time they hit the silver screen. So, are these changes good or bad? As with anything else, it depends. Some of the changes were able to breathe new life into characters that were mostly a joke in the comics. Other changes, however, turned off all the fans of a comic character when they were horrified at the eventual changes.

How can you tell which changes are good and which changes are bad? That’s a solid question: fans like to argue among themselves about which changes were justified and which changes should be stricken from the MCU altogether. And it can be tough to wade through these online comment wars to find the truth. That, of course, is where we come in! We’ve pored over all of the changes made to the MCU to help determine which changes were great and which were underwhelming. Then we put it all together in this convenient and comprehensive guide. Ready to learn the secrets of this on-screen universe?

20 LOVED: STAR-LORD’S DAD

In Guardians of the Galaxy: Vol 2, we get to see Star-Lord resolve the galaxy’s biggest daddy issues. However, it was very different in the comics: instead of his dad being a living planet, Star-Lord’s father is a pretty generic evil dictator and all-around jerk.

This ended up being a positive change because it helped raise the stakes and make the story larger than life. It also gave Star-Lord a really nice arc of choosing to be a human being instead of choosing to be a god-like alien. In this way, he joins the Marvel club of those carefully measuring concepts such as power and responsibility.

19 HATED: ULTRON'S ORIGIN

In Age of Ultron, we see Tony Stark build an A.I. that goes rampant and nearly destroys the world: Ultron. In the comics, however, Ultron was created by Hank Pym, the original Ant-Man. Ultimately, this ended up being one of the worst changes from the comics.

First, it seems very backwards for Tony’s character development. In Iron Man 3, we see him seemingly getting over his need for automated defenses, going so far as to destroy dozens of suits. Now, he goes back on this and endangers the whole world. This change also removes some of the depth of Hank Pym, making him more of a generic “grumpy old man” than a true outcast hero.

18 LOVED: FUNNY THOR

In some ways, Thor has had the most on-screen changes. In fact, the Thor of Ragnarok is practically unrecognizable compared to the Thor of both the early MCU and the comics. He is now funny, quippy, and generally as likely to bring the laughter as he is to bring the hammer.

This is a major change, but it’s one that the vast majority of fans loved. It makes all of Thor’s scenes more enjoyable and helps lighten the mood of the otherwise epic stakes. Plus, Chris Hemsworth is naturally hilarious, and this gives him an opportunity to showcase that talent to the world.

17 HATED: SCARLET WITCH AND QUICKSILVER

Quicksilver and Scarlet Witch in Avengers- Age Of Ultron

In the comics, Scarlet Witch and Quicksilver have complicated origins. They are mutants, and depending on who is doing the writing that month, they are the children of the X-Men foe Magneto. In the MCU, they are not mutants but successful experimental subjects empowered by Loki’s staff.

This is a poor change because none of it made much sense. How could a staff powered by the Mind Stone suddenly give people magical powers? Why didn’t Hydra create an army of villains with the staff while they had it? And why the heck did Thor leave the staff on Earth? Ultimately, this change led to a lot of confusion for fans.

16 LOVED: KILLMONGER MOTIVATION

Killmonger in Black Panther

Black Panther was a Marvel movie that took the world by storm. This was largely because the villain, Killmonger, was absolutely compelling, and it was difficult to not sympathize with his motivations to try to use force and create a world of more equality.

However, this was very different from the comics. In the comics, Killmonger had no relation to Black Panther, was enslaved as a child by Klaw, and had a super academic background instead of a mercenary background. By making various changes to the character, the MCU made everything seem both more modern (evoking things like the Black Lives Matter movement) and more classical (their fatal family struggle echoes Shakespeare as much as it does Stan Lee).

15 HATED: COSMIC SKULL

In Captain America: The First Avenger, the Red Skull suffers an ambiguous fate. While holding the Cosmic Cube, he basically disappears and ultimately drops the cube. Was he dead? We later find out that Red Skull was sent to a distant planet and somehow became the guardian of the Soul Stone.

This never happened in the comics, and it was a pretty bad change. None of it really made much sense: how did the Cube know which planet to send him to? How did he survive alone on an empty planet? And where did he learn all the secrets of the Stones? This cool reveal ultimately ended up being very confusing.

14 LOVED: AVENGERS ROSTER

As every comics nerd has spent years telling you, the MCU Avengers original lineup is very different from that of the comics. On-screen, we started with Captain America, Iron Man, Thor, Black Widow, Hawkeye, and Hulk. In the comics, the original lineup was Iron Man, Thor, Ant-Man, Wasp, and the Hulk.

Ultimately, the MCU change to the lineup was for the best. While Ant-Man and the Wasp are cool, their powers didn’t have the “wow” factor necessary for that first movie. And it’s frankly impossible to imagine the MCU Avengers without Captain America. Once Avengers: Endgame wraps up, it will be interesting to see what the new heroic lineup looks like.

13 HATED: THE MANDARIN

The Mandarin in Iron Man 3

Iron Man 3 is a very divisive movie. This is due in large part to changes made to the Mandarin. In the comics, the Mandarin is Iron Man’s primary nemesis and powered by ten magical rings that help him fight the old shellhead. In the MCU, the “Mandarin” was actually just a fictional character portrayed by an inebriated Englishman.

This was a terrible change because almost nobody liked it. Comics fans felt insulted by the major change while casual movie fans wondered why such a cool character was squandered. In fact, this portrayal was so unpopular that the MCU later retconned things to say there was a real Mandarin out there and he was displeased by the pretender we saw.

12 LOVED: VULTURE

Michael Keaton as the Vulture

Vulture was a very different character in the original Marvel comics. He was basically an old man in an embarrassing bird costume who could fly, and he used those powers for petty theft. Needless to say, almost everything about this was changed for Spider-Man: Homecoming.

Overall, these changes were very positive. Making Vulture more technological and giving him a connection to Tony Stark helped make everything more personal; moreover, the revelation that he so closely orbited Peter Parker’s life raised the stakes in a truly exciting way. All in all, fans were left absolutely hoping they’d see this compelling villain on-screen once again.

11 HATED: ZEMO

In Captain America: Civil War, the villain Zemo is very sympathetic. He is basically just a normal guy out to get revenge for the demise of his family in Sokovia. In the comics, Baron Zemo had a wacky mask, a talent for time-traveling, and a bad habit of trying to help the bad guys win World War II.

While it’s true that the wacky and more colorful Zemo would have been out of place in the MCU, the Zemo we got was a bit boring. He is sympathetic, but never seemed to pose a real threat to our heroes. Basically, this is an example of what happens when your big villain is a master manipulator -- no more and no less.

10 LOVED: HELA

Hela holding Mjolnir in the MCU

In Thor: Ragnarok, Hela continued the fine MCU tradition of changing the villains from their comic origins. In the comics, she alternated between being a daughter of Loki and a kind of magical creation of Loki’s. In the MCU, she is firmly established as being a black sheep of Thor’s family and a daughter of Odin.

Overall, these changes were really great. They helped to add some dark depths to Odin as we glimpsed what a conqueror he used to be and things were also much more personal when it came to Thor and Loki having to take on their long-lost sister. Finally, being a daughter of Odin helped explain how much raw power Hela seemed to wield.

9 HATED: MJ

Zendaya's Michelle Jones "MJ" sitting at a desk and sketching in Spider-Man: Homecoming.

Fans were a bit confused for most of Spider-Man: Homecoming. Were we really going to have an entire Spider-Man movie without Mary Jane? Towards the very end, we were hit with the big reveal: Peter’s friend Michelle is known as “MJ” to her friends.

It made for a cute reveal, but this seems very problematic as far as comic changes go. It seems like if she is going to be the MJ of the MCU, then she will have little to nothing in common with the Mary Jane of the comics. Fans hoping to see this fan-favorite character on-screen were, of course, a bit disappointed.

8 LOVED: OUTLAW STAR-LORD

One reason why Star-Lord is such a popular MCU character is that he is a character archetype. “ Cool Outlaw” is something audiences both recognize and instantly appreciate. However, this is different from the comics. In earlier appearances, Star-Lord was much more like a space cop than an outlaw.

Overall, this was a very good change. It gave Star-Lord an extra level of coolness, and it helped pave the way for other characters to fulfill the “space cop” role. In fact, a small (but very loud) contingent of fans are hoping we’ll be getting a Nova movie any day now for more space cop shenanigans.

7 HATED: STORMBREAKER

Sometimes, changes from the comics are bad for unexpected reasons. Take Stormbreaker for instance. Thor’s big Thanos-ending weapon had a completely different origin in the comics, belonging first to fan-favorite character Beta Ray Bill. It’s sad but understandable that we get no Bill, but this change was still bad.

Why? Mostly because Thor’s side story is pretty boring. We enjoyed the Peter Dinklage cameo, but watching Thor slowly leveling up his Blacksmith skills is about as boring as Infinity War got. Honestly, we’d have been happy if this plot had been nixed from the film altogether, but maybe it will pay off more in Endgame.

6 LOVED: THANOS MOTIVATIONS

Josh Brolin as Thanos

If we’re being honest, Thanos had some crazy motivations in Infinity War. Given the chance to rewrite all of reality, he decided to wipe out all life because there are only so many resources. Geez, Thanos -- you could have just made extra resources instead! However, this motivation was a big change from the comics.

In the comics, Thanos was in love with Death. Like, an actual woman who represented the concept of Death. But she kept friendzoning him, and he did crazier and crazier things to impress her, including wiping out countless lives. This would have been utterly insane to see on-screen, so we’re happy Thanos got a different motivation.

5 HATED: ELDER ANT-MAN

Ant-Man and the Wasp are fun additions to the MCU. However, the ones we focus on are basically the second generations of these heroes. As we see, the original Ant-Man and Wasp were heroes back in the day, eventually retiring after Wasp was seemingly lost in the Quantum Realm.

In the comics, these characters interacted more with the Avengers and were even founding members of the super team. We can’t help but feel it was a poor change to make them elder statesmen instead of contemporary heroes. The arguments between Hank Pym and Tony Stark by themselves would have been worth the price of admission.

4 LOVED: NO DEMON IN A BOTTLE

In the comics, Tony Stark is an alcoholic -- it’s a major part of the character’s history and a daily struggle. In the movies, however, Tony is content to be a fun drunk, and we’ve never gotten truly close to an on-screen adaptation of Tony’s “Demon in a Bottle” storyline.

Ultimately, this is a change for the better. Part of Tony Stark’s charm is seeing him be the life of the party, and nixing the alcoholism helps with that. Also, there sadly isn’t much time to deal with that kind of inner struggle on-screen when there are so many external threats to deal with.

3 HATED: INHUMANS

Inhumans

While this looks to have changed recently, the MCU originally had a really big hurdle: they didn’t have the rights to use “mutants” such as the X-Men. The workaround was that, for a time, they embraced the Inhumans instead as a source of on-screen mutations.

This ended up being a poor change. While we got some cool Inhumans stories from Agents of S.H.I.E.L.D., the actual Inhumans show was pretty bad. And now that mutants are coming to the MCU after all, the presence of the Inhumans is even more of a waste. Let’s just hope we can avoid too many on-screen fights between the two groups of mutations.

2 LOVED: NICK FURY

If you didn’t already know, the MCU Nick Fury is very different from the one in the comics. The one in the comics, for instance, is very white. How white are we talking? Heck, David Hasselhoff portrayed him in a TV movie! Fortunately, the MCU took its cue from the Ultimates comics and cast Samuel L. Jackson in the role.

This is arguably one of the best possible changes from the comic. Jackson brings a special energy to every scene, and his intensity makes some of the sillier moments more believable. At this point, it’s almost impossible to imagine an MCU with Jackson in it.

1 HATED: CIVIL WAR CHANGES

We finally got to see an on-screen adaptation of the classic "Civil War" story. However, it was very different. In the comics, the big issue was forcing all the masked heroes to register with the government and surrender their secret identities. In the MCU, where almost all heroes have public identities, this was a non-issue.

Ultimately, the change was pretty bad. It seemed to be far lower stakes than in the comics, as the issue was “deal with politicians or don’t” instead of “endanger your family or don’t.” Sadly, it seemed like just a bad excuse to make onscreen heroes fight each other. This was doubly sad because the original story was much more nuanced.