By the time Phase 2 of the MCU kicked off, the bold plan for the cinematic universe of Marvel characters was already a proven success. With that success can the confidence to take risks with new characters and reinvent existing heroes. The universe continued to grow with more heroes and villains added to the universe.

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While heroes like Captain America and Iron Man were appropriately in the spotlight, there were other character fans wish they could have seen more. On the other hand, some characters proved to wear out their welcome with fans or never really caught on in the first place.

10 Not Enough: Thanos

At the end of The Avengers, they teased the looming threat of popular comic book villain Thanos. Fans were thrilled to see the Mad Titan getting ready to take on the team of heroes, but it turns out that wait would be much longer than they expected.

As the next Avengers movie focused on Ultron, Thanos was only teased within Phase 2. His quick appearance in Guardians of the Galaxy felt too shot to be worth it, especially since he didn’t at all come off as the threat that had been promised.

9 Too Much: Aldrich Killian

Despite a lot of success, Phase 2 of the MCU started to show a continuing problem with the villain in their films. With one or two exceptions, all of the bag guys had been largely forgettable so far. Iron Man 3 delivered yet another lackluster baddie in the form of Aldrich Killian.

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While the twist involving The Mandarin worked for some better than others, it distracted from the opportunity to build Killian into an interesting and worthwhile bad guy. In the end, he seemed mostly tacked on.

8 Not Enough: Maya Hansen

As it turns out, Killian’s role as the villain in Iron Man 3 was somewhat tacked on as the original plan was for Maya Hansen to be the movie’s big bad. Maya’s involvement with the bad guys is still present in the movie and her motivations are much more interesting than Killian’s were.

Disney execs apparently refused to allow a female villain in the role so Killian was put in the villain role and Maya’s character was rewritten in an awkward way. If they had gone with the original plan, she could have been a memorable villain.

7 Too Much: Jane Foster

The romance between Jane Foster and Thor in the first Thor movie didn’t do much for audiences. Despite the charm of Natalie Portman and Chris Hemsworth in their respective roles, this romance was forced and these characters felt incompatible.

Instead of cutting their losses and moving on as they would do later, Thor: The Dark World decided to double-down on the romance story, making it much more integral this time around. Once again, Jane Foster came off as the wrong partner for Thor and the romance landed with a thud.

6 Not Enough: Malekith

Instead of wasting time with an uninteresting romance, Thor: The Dark World should have been dedicating more time to its villain who was sorely in the need of some character development. In the long line of lackluster MCU villain, Malekith is easily the most forgettable.

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The frustrating thing about the character is that there could have been something interesting there. It has been said that a lot of his backstory and motivation were cut out of the final product which left him as a lame foe.

5 Too Much: Loki

Tom Hiddleston helped turn Loki into the MCU’s best villain to date and a true fan-favorite character. In fact, his popularity began to overshadow his heroic brother which became a problem in Thor: The Dark World.

While bringing Loki back for the sequel was an understandable move, it seems like the story is almost shaped around him. And while he is prominent in the movie, it doesn’t add much interest to the character in the end.

4 Not Enough: Hulk

The Hulk was a bit of a question mark in Phase 1 with the lackluster The Incredible Hulk and the recasting of the role. But Mark Ruffalo’s performance and the Hulk’s involvement in The Avengers quickly won over fans.

That’s why it was such a letdown to see that Hulk would not be getting his own solo film in Phase 2. After showing that the character could be interesting and entertaining on the big screen, it was disappointing to have to wait until Avengers: Age of Ultron to see him in action again.

3 Too Much: Quicksilver

Avengers: Age of Ultron decided to bring in a couple of key Avengers members from the comics with Scarlet Witch and Quicksilver. The brother and sister team started as allies of Ultron before joining the heroes to take down the evil robot.

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It was clear Joss Whedon found Scarlet Witch to be an interesting character. The same cannot be said of Quicksilver. The character felt like he was just there to chew up time until his death which was more about his sister than about him. The fact that he was an Avengers and no one remembers him speaks to how unnecessary he was.

2 Not Enough: Vision

As if Quicksilver and Scarlet Witch weren’t enough, Age of Ultron also decided to bring in Vision to join the team. Vision is important to Ultron’s story and once he is onscreen he is a fascinating character. The problem is that he is introduced in the third act.

There is so much the film could have trimmed out to make Vision a part of the story earlier on. To throw him into the last act feels very rushed and gives the audience very little time to get used to this complex character.

1 Too Much: Ultron

Ultron is a very prominent and formidable foe for the Avengers in the comics. The first trailer for Age of Ultron hinted at this terrifying creation brought to life with a menacing performance by James Spader. The end result was something quite different.

Whedon put Ultron front and center with long quippy monologues that made the character much goofier than expected. It never felt quite right and the character could have benefited from being scaled back to leave more to make him more ominous rather than a sarcastic robot.

NEXT: Avengers: Age Of Ultron: 5 Things It Got Right (& 5 It Got Wrong)