The Marvel Cinematic Universe has had a lot of amazing concept artists work with its characters and worlds. The concept art produced for any movie is a key part of the production process and one that can influence the final product greatly.

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While sometimes the final film includes the best of the best in terms of the art put forward, other times, concepts had to be left out that were superb! Here are five pieces of concept art that we're grateful made the cut and five that we're glad never saw the big screen.

Grateful They Cut: Alternate Ego Look

Ego is an interesting character and one, of course, driven by his own obsession with spreading himself across the galaxy. If he was to come across as a father figure to Peter Quill, he had to look like he could make a great dad.

The concept art here successfully demonstrates the power of the character but would not have been right for the story. He's a bit too ethereal to ever be trusted, coming across more like a celestial than he should.

Wish They Kept In: Hawkeye's Mask

One of the criticisms of Hawkeye throughout his MCU career is that he hasn't looked much like a superhero or like his comic book counterpart. One of the things he was missing was a good mask.

While his time as Ronin showcased just how great Clint Barton could look with a full hero costume, this mask concept art really would have been perfect for the final film. What's more, the goggles could have acted in a tactical fashion.

Grateful They Cut: Spidey's Original Suit

Firstly, the Ben O'Reilly Spider-Man costume is absolutely excellent. Secondly, the final version of Peter's homemade suit is also fantastic. That's exactly why it's great that this never made it to the final film.

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From the blue jacket to the unique gloves and belt, this is perfect for when Ben O'Reilly is introduced to the big screen. Until then, Peter must stay authentic to who he is, which the homemade suit is perfect for.

Wish They Kept In: An Accurate Mantis

The design for Mantis is actually pretty bland in the final films. She more or less looks like a human with bigger eyes and some antennas. The assumption is this was so fans didn't get her confused with Gamora.

But, the concept art here shows how different the character could have been, with face markings and a completely unique costume. It would have been far more visually interesting to have this version of the character.

Grateful They Cut: The Original Valkyrie

Valkyrie was at some stage planned to appear much sooner in Thor's world than she actually did. The concept art put forward for her original appearance is far too expected for a character like this.

Sure it has an angelic like quality that match the Pegasus the character is known to ride, but it really doesn't fit with the tone of the rest of the MCU. In fact, this is a design that belongs more in a video game.

Wish They Kept In: Mutant Scarlet Witch

If the creative team wanted to bring mutants into the MCU, this is the perfect way to include the Scarlet Witch in that. This feels like an X-Men look and brings in elements from her classic comic costume.

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The tones of red and black are absolutely perfect, as is the headpiece that nicely brings this costume together. In some ways, it's surprising there isn't a cape for good measure. Hopefully, this design is brought back in the future.

Grateful They Cut: Familiar Wasp

The Wasp's costume in the final film is quite unique. Although the colors could be turned up a little more, it's a design that works well in the universe and sets her apart from other heroes.

The design here looks far too much like Ant-Man and is clearly linked to the original Wasp's design. It would be difficult to keep the characters apart, plus the helmet and stingers stand out for all the wrong reasons.

Wish They Kept In: Classic Star-Lord

Star-Lord's MCU design is pretty fun but it's nowhere near what the original concept art was for him. This feels much more like a steampunk type design, complete with a more comic accurate helmet.

It would have been fascinating to see this concept art chosen for the character and see what direction this would have taken the rest of the team. There's no telling how the final product would have turned out!

Grateful They Cut: Ultron's Final Form

Ultron was a flawed villain in that he became quite repetitive to the first enemies that the Avengers fought. But, the idea they could all combine into a larger robot would have been even worse!

It looks in some ways like the Leviathan that Iron Man made short work of previously, but is also reminiscent of so many other movie villains that eventually combine in this way.

Wish They Kept In: A Unique Zola

The version of Zola in the computer was pretty unique, but that doesn't mean that this iteration wouldn't have been much better. There's always a chance the character can return in the future.

By using this hologram technology on a robotic body, it's as if the character has been given an upgrade. Hopefully, the MCU can see this concept art come to life too!

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