In 1963, a revolutionary new breed of hero emerged in the pages of X-MEN #1. These strange men and women each possessed a special "mutant" gene, granting them incredible powers and abilities. Since those early years, Marvel's mutants have exploded into a worldwide pop-culture phenomenon. From a single comic book, the X-Men went on to star in a diverse line of titles featuring mutants of every type imaginable, as well as a pair of top-rated animated series and two hit movies. Featuring more than 350 fully illustrated biographies, the X-MEN ENCYCLOPEDIA is a comprehensive guide to these world-famous Marvel Comics characters their mysterious origins, their incredible powers, their titanic struggles and their hidden tragedies.