The event launches in X-Men: Legacy #245 next month and is being written by long-time X-Men scribe Mike Carey with pencils from Clay Mann.
Originally announced through a string of teasers, Marvel eventually revealed that the crossover is set in an alternate universe where the X-Men never had the chance to form and mutants have been hunted to near extinction.
Carey has promised that, despite the nature of the series, it will still have repercussions on the mainstream X-Men universe.
Among the characters depicted in the preview images are former Generation-X member Chamber, founding X-Man Angel and a character who strongly resembles X-Force's Warpath.
X-Men: Legacy #245 is due to be published on February 23.