Countless members of the X-Men have gotten the big screen treatment, including iconic names like Wolverine, Cyclops and Jean Grey. However, the villains often lived in the shadow cast by Magneto, whose compelling story pushed the narrative for multiple movies. While seeing Magneto's battles against Professor Xavier or his tragic descent into villainy was exciting, other villains had a unique story and abilities that weren't properly explored. A great example of this was Mystique, who was more than a shapeshifter, being a mercenary with a tragic past that extended far beyond her powers. But she wasn't the only villain that deserved a proper exploration of their story.
Source:https://www.cbr.com/first-x-men-movie-toad-prehensile-tongue/