Before Deadpool hit theaters, most people had likely never heard of Negasonic Teenage Warhead. She was an obscure character, having only made a total of three appearances in the comics. To make things worse, she died in two of those appearances and wasn't even real in the third.
Because Negasonic Teenage Warhead was so obscure, the creators of Deadpool had a lot to work with when it came to reinventing her for the screen. They even tried out a number of different looks for the character, as seen in recently revealed concept art.
The concept art by artist Joshua James Shaw shows nine different iterations of the character's core look, along with three different takes on Negasonic Teenage Warhead in an X-Men costume. Not only are different goth-inspired outfits included in the concept art, but different hairstyles are as well. In the end, of course, little if any of these designs made their way into the final look of the character. Deadpool's Negasonic Teenage Warhead had a shaved head and wore a loose-fitting long coat for most of the film, going in the opposite direction from the big hair and more form-fitting options considered in the concept art.
In addition to the concept work on Negasonic Teenage Warhead, Shaw has also posted costume concepts for Deadpool himself as well as a concept piece from the fight between Colossus and Angel Dust. His portfolio also includes concept pieces for X-Men: Days of Future Past, the Halo video game series and the Far Cry series, among others. You can see more of Shaw's portfolio here.
It's always interesting when concept art differs significantly from the final version of the product being created. It provides fans with a better look at how the design progressed, and in the case of Deadpool it shows a willingness to move away from concepts that might be sexier to something that just works better within the film. Though some of the designs are closer to the comic character's look than what we got in the Deadpool film, the film version worked better with how the character was portrayed.
The look in the film also worked well with her power set, which is drastically different than what she had in the comics; despite having a relatively hardcore-sounding name taken from a Monster Magnet song, the comic version of Negasonic Teenage Warhead was a telepath whose main power was seeing visions of the future in her dreams. In the film, this was abandoned in favor of giving her a power more befitting her name (which was essentially taken from the mutant Cannonball) and an attitude to match. Most fans will likely agree that this was a major improvement.
Deadpool is now in theaters; X-Men: Apocalypse opens on May 27, 2016; Gambit sometime in 2017; Wolverine 3 on March 3, 2017; and an unannounced X-Men film on July 13, 2018. The New Mutants and Deadpool 2 are also in development. X-Force is rumored and should enter development soon.
Source: Joshua James Shaw