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X-Men: The Last Stand (2006) More at IMDb Pro »

Alan Cumming was reportedly uncomfortable with the long hours he had to take with the Nightcrawler makeup in X-Men 2, but still planned to return for X-Men: The Last Stand when Bryan Synger was attached. When Brett Ratner took on role as director, Alan Cummings left the project. Thoughts of replacing Alan Cummings were considered but the part for Nightcrawler was so minimal, however, that the studio felt it was not worthwhile to go through the long and costly makeup process, and the character was cut.

Nightcrawler's absence was explained in in the X-Men: The Official Game. At some part of the story of the game, Nightcrawler tells Xavier he does not want to be an X-Man, for their lives are too violent and he is a peaceful man. Xavier tells him he is always welcome in the Mansion, and Kurt leaves, explaining his absence in X-Men: The Last Stand.

Yes. In the first film she was played by Sumela Kay, In the second she was played by Katie Stuart and in the third, she was played by Ellen Page.

In the first and second, her characters were more like cameos. Her role was bigger in X-Men:The Last Stand.

While we do see a sentinels head in the beginning of the film. The original outline of the plot for X-Men 3 when Singer was attached was to be the sentinels as well as the Phoenix.