Marvel's merry (and dysfunctional) band of mutants have been a big part of our summer blockbuster lineup since the turn of the century. Since their debut, they've been through a lot of changes, from costume redesigns. to messy alternate timelines, to Wolverine jumping up the age rating scale. (None of us will ever be the same again after hearing Professor X drop so many F-bombs.) Like any big budget movie series, the X-Men films go through lengthy development stages to decide how characters, props and set pieces will look. Sometimes the finished results are impressive even if they deviate from the comics.

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The futuristic Sentinels in Apocalypse, for instance, were about as far from their classic look as possible, but they looked all the more terrifying for it. Sometimes the creatives powers that be manage to translate design elements from page to screen faithfully to great effect. Characters like Mystique and Nightcrawler, who have two of the most distinctive looks in the comics, have remained satisfyingly on point on-screen. But, sometimes seeing what we could have had in the concept art vs. what we actually got is a big disappointment. Here is a collection of costumes and character designs from the history of the X-Men movie series that never made the final cuts.

15 DEADPOOL

Deadpool (Unused X-Men Concept Art)

It's hard to think of a more divisive comic book character redesign for a film than Deadpool's in the first solo Wolverine movie. Just to prove the point, the "Like" bar under the YouTube video that the studio responsible uploaded is almost an even split of "Likes" and "Dislikes." Though Deadpool appeared pretty (unusually) normal-looking in his first appearance, hopes of something comic-accurate were dashed later when a fleshy and muted monstrosity showed up.

Looking through the exhaustive list of 82 alternatives that Studio ADI came up with it looks like we could have gotten something either slightly better... or a whole lot worse. But, as the creators note in the video's description: "It was our job to satisfy the many creative voices [...]  We'll never satisfy everyone with a design."

14 QUICKSILVER'S STEREO BELT

Quicksilver Stereobelt

How cool is this? Magneto's speedster son wasn't in Days of Future Past for very long -- true to his abilities -- but his ultra-cool, 70s make-over left a quite an impression on fans both old and new. From looking at concept designer, Henry Fong's artwork for the character not much changed between the conceptual and finished look in the film, right down to Evan Peters' shaggy, silvery hair.

Apart from the goggles, the other accessory that caught fans' attention was Pietro's customized "stereobelt," which, as you can see from Henry's wonderfully detailed illustrations, could have looked a lot quirkier. The one we see Quicksilver rocking in the film is a lot slicker with an almost Darth Vader feel to it. The worn, brown leather and stickers in the concept art make it look a lot more home-made.

13 WOLVERINE

Wolverine Concept Art

Though you absolutely can't fault Hugh Jackman's portrayal of Wolverine, it's fair to say a lot of liberties were taken when translating the character from page to screen. James Howlett gained several inches in height, learned how to use a comb a bit better, was a lot less stabby, and most notably, wouldn't be caught dead wearing yellow spandex.

Judging from this early concept from concept artist, Tim Flattery you can see that the studio did consider a more faithful version at one time, though. Not only is the character dressed in a costume that very closely resembles his classic one but his hair is much wilder too. More shocking though is the blood dripping from his claws, perhaps indicating a higher age-rating might have been considered as well.

12 JEAN GREY

Jean Grey Concept Art

This piece of concept art of the young Jean Grey tells us two big things that nearly happened in Apocalypse: one, we nearly got the more colorful costumes carried over from First Class, and two, we nearly got Elle Fanning in the role rather than Game of Thrones' Sophie Turner. In fact, for Fox to get as far as commissioning artwork based on Fanning means she must have been very close indeed.

Perhaps the studio thought it could save some money on ginger wigs after presumably blowing most of the hair and make-up budget painting Oscar Isaacs' blue every day. The art was produced by Allen J. Villanueva in collaboration with long-time X-Men costume designer, Louise Mingenbach. Allen also produced artwork of Sophie Turner in the same blue and gold suit.

11 SENTINELS

Sentinel Concept Art

Though the movie versions of the mutant-hunting sentinels didn't bear a huge resemblance to their comic book counterparts (other than a nod to their purple coloring and yellow eyes early on) the futuristic upgrades were satisfyingly terrifying -- nightmarish monsters to suit a nightmarish possible future. The fact they also looked more like humans than Transformers didn't help either.

This concept art from Maciej Kuciara proves the studio was spoilt for choice with creepy sentinel designs, with some looking blockier than the scaly texture they ended up with. Director Matthew Vaughn said that the scales were not only supposed to resemble Mystique but the robots were originally planned to also borrow from Rogue's powers too. It's interesting to think where this aspect could have taken their design.

10 TRASK'S CAMEO

Trask X-Men Apocalypse

Yes, according to this piece of atmospheric concept art, Peter Dinklage's Bolivar Trask was at one point supposed to make a cameo in the follow-up to Days Of Future Past. In the artwork by illustrator, Bartol Rendulic you can make out the unmistakable silhouette of Trask disembarking (or possible boarding) a jet with Jennifer's Lawrence's Mystique aiming a gun at him.

This deleted scene was going to be one of a few set on Stryker's base with the mastermind of the sentinel program probably only making a brief appearance. It's not known why the sequence was scrapped but the most likely culprit was probably that the film's budget couldn't justify an inconsequential plot detail like this one. Still, it would've been a treat for fans to see Dinklage reprise the role.

9 BEAST AS TRASK'S PILOT

Beast's Pilot Helmet

From other pieces of concept art released after Apocalypse hit theaters, we know that Peter Dinklage's Bolivar Trask was, at one point during the development process, going to make a return in Apocalypse. This concept art from Bartol Rendulic further cements his involvement, depicting Beast in a pilot's helmet labeled as "Trask's Plane: Pilot's Helmet."

This leaves us with a lot of questions as to what role the antagonist was going to play amongst all the world-ending drama. Did he align himself with Weapon X? Was he a founding member? Or did he work independently to round up the younger mutants? Though it would have been interesting to see the film explore these ideas, they were probably cut so as not to distract from the main plot too much.

8 HAVOK

Havok Concept Art

It was exciting for comic book fans to see another Summers brother finally introduced to the X-Men cinematic universe in First Class, though the alternate timeline means that Alex is the older brother on screen, taking Scott's canonical place as one of Xavier's original X-Men. Lucas Till's suit in First Class was designed with training wheels -- the disk on the chest helping to focus his energy blasts while also nodding to the character's comic book costume.

This dramatic piece of concept art from Alex Mandragjiev shows off a possibly more competent version of the character with a darker edge. The circular chest piece is still just about visible and you can also see more armor details lining the suit's exterior. Most notably though, he's got that distinctive, blonde hairdo he often sports in the comics.

7 BANSHEE

Banshee Concept Art

Banshee's appearance in First Class was all too brief, and after it was revealed that he'd become one of the many casualties of Trask's war on mutants during Days of Future Past, his role in the movies seems unlikely to be extended for the foreseeable future. This unused concept art produced by Alex Mandragjiev gives us a glimpse at a Banshee who looks badass enough to have made it out alive.

Banshee was played by Caleb Landry Jones, whose natural red hair makes him a dead-ringer for the young Sean Cassidy. The only thing missing was the Irish green on his suit, though from this artwork it looks like that was never really considered at any stage of the film's development. It may just be the lighting but this Banshee's face also bears an uncanny resemblance to his villainous mutant brother, Black Sean Cassidy.

6 TEENAGE X-23

X-23 Concept Art

One of the many things that made Logan such a successful movie was 11-year-old actress, Daftne Keen. Though she had very little to say throughout most of the film, her actions -- and ferocious facial expressions -- spoke louder than words ever could. Obviously, her young age only added to the shock of the ultra-violence but early concept art reveals that an older version of Laura was considered, too.

These variant designs from visual effects specialist Aaron Sims depict a classically, moody teenage girl with very heavy goth taste -- leather, miniskirts, eyeliner and excessive belts. Director James Manigold explained he pushed to lower the character's age to avoid the movie feeling, "like a CW show [...] I wanted to confront Logan with what he was most frightened of, which was the idea of being [...] a real Dad. Not to an unruly teenager, but to a child."

5 JUBILEE

jubilee

Although Jubilee popped up repeatedly in the background of the original trilogy of X-Men movies (you'd be forgiven for not remembering her), she didn't make her first proper appearance until Apocalypse. Played by Lana Condor, it was great to see Jubilation Lee in all her '80s, pink and yellow glory. But, at one point, the fun-loving mutant was planned to appear before this in Days of Future Past.

This concept art from artist Phillip Boutte Jr. in collaboration with long-time X-Men costume designer, Louise Migenbach, depicts a much grittier-looking version of the character with actress Jamie Chung as the model. In the midst of a sentinel war, it makes sense that Jubilee would shed her colorful wardrobe for something more low-key. The headband provides the only reference to her classic costume from the comics.

4 JUGGERNAUT

juggernaut concept

He's the Juggernaut, bitch. After Vinnie Jones', uh, interesting performance as Cain Marko in X-Men 3: The Last Stand, Professor X's stepbrother has yet to make a return to the film series. But, concept art released after Days of Future Past hit cinemas by Anthony Jones reveals that the rampaging mutant very nearly bulldozed his way back into the franchise.

The artwork uses Vinnie as a model with the costume design very similar to the one he donned in X3. Key alternations like replacing his domed helmet with a red hood and mask are a good compromise between believability and honoring his comic book roots. Apparently, young Juggernaut would have played the role that Quicksilver's character does in aiding Magneto's prison break.

3 THE WHITE QUEEN

Emma Frost Concept Art

Even with special effects being at the level they are these days, pulling off Emma Frost's diamond skin must still present a challenge for most. In the comics, the effect varies hugely depending on the artist but usually, her organic diamond form resembles something akin to Colossus' with a little more sparkle. From this concept art, it looks like artist Jerad S. Marantz had several cracks at it.

The look of Emma's secondary mutation transformation that January Jones sported in the film was perfectly fine, if not a little... obvious. She quite literally looked like a cut diamond. These alternate options are a bit more creative and skin-like, with the diamond spikes making it look more clearly like a defense mechanism rather than just a human engagement ring.

2 APOCALYPSE

Apocalypse Concept Art

To say that the world's first look at Oscar Isaacs as Apocalypse wasn't a great success would be an understatement. Supervillains are the backbone of superhero stories, so to feature one whose appearance invites laughable comparisons to Power Rangers characters and bad cosplay makes a film's marketing an uphill struggle from then on to win back credibility.

Many fans felt the ancient mutants' looks didn't improve much when the film was released, which just makes this imposing, variant design from concept artist Jerad S. Marantz even more frustrating to see. The armor is far sleeker than the clunky stuff Oscar had to wear, and -- more disappointingly -- it proves that Apocalypse's distinctive facial features from the comics could have been pulled off in real life.

1 STORM

Storm's hair-volution has been getting tantalizingly close to everyone's favorite, '80s punk rock look throughout the film series' history; from her long locks in X-Men and X2, to her cropped bob in X3, and her pixie-cut in Days of Future PastFinally, in Apocalypse, Alexandra Shipp rocked the mohawk as a younger version of the character.

The only thing she was missing was the other 90% of the look. It was close but no cigar. Annoyingly, this fantastic concept art from Phillip Boutte Jr. and Louise Migenbach shows just how close we were to seeing Storm decked out in all her biker-chick-from-the-future glory. Though there's no mohawk, the addition of the "boy toy" belt buckle more than makes up for it.

Which of these unused concept art pieces do you wish had ended up in the films? Let us know in the comments!