Another new X-book released at the time was X-Force, featuring the characters from The New Mutants, led by Cable; it was written by Rob Liefeld and Fabian Nicieza. Internal friction soon split the X-books' creative teams. In a controversial move, X-Men editor Bob Harras sided with Lee (and Uncanny X-Men artist Whilce Portacio) over Claremont in a dispute over plotting. Claremont left after only three issues of X-Men, ending his 16-year run as X-Men writer. Marvel replaced Claremont briefly with John Byrne, who scripted both books for a few issues. Byrne was then replaced by Nicieza and Scott Lobdell, who would take over the majority of writing duties for the X-Men until Lee's own departure months later when he and several other popular artists (including former X-title artists Liefeld, Portacio, and Marc Silvestri) would leave Marvel to form Image Comics. Jim Lee's X-Men designs would be the basis for much of the X-Men animated series and action figure line as well as several Capcom video games.
Bryan Singer , who had directed the two previous films, X-Men (2000) and X2 , decided to leave to work on Superman Returns , as he had not even defined the storyline for a third film. Matthew Vaughn , who was initially hired as the new director, left due to personal and professional issues, and was replaced with Ratner. Filming took place from August 2005 to January 2006 with a budget of $210 million, and was consequently the most expensive film at the time of its release. It had extensive visual effects created by 11 different companies.