Trivia: In the bar, when Wolverine dismisses Xavier's offer to join him, Hugh Jackman ad-libbed the line "go f*** yourself." The line was originally written "F*** off." Later, in "Days of Future Past", Xavier remembers the line as "F*** off", not "go f*** yourself." (00:48:15)
Trivia: Jennifer Lawrence suffered an allergic reaction to her Mystique makeup.
Trivia: Hugh Jackman agreed to a cameo with two conditions - that money would be donated to his child's school, and that he be allowed to swear.
Trivia: Director Matthew Vaughn was originally slated to direct "X-Men: The Last Stand," but dropped out of that film over worries about the rushed schedule. He finally returned to the series with this film.
Trivia: There was going to be a scene where Xavier and Emma Frost had a mental "battle" where they would fight inside their minds, but the idea was dropped. A similar concept was eventually used in "X-Men: Apocalypse," in which Xavier and Apocalypse battle inside of their minds.
Answer: It is shown in X-Men: Days of Future Past that Hank made a serum that can help him walk.