The end of an era for the X-Men! The original team, now called X-Factor, takes center stage when Proteus returns from the grave. But when Apocalypse strikes, infecting Cyclops' son Nathan with a deadly virus, Cyclops must make a bitter sacrifice! And the current X-Men return to Earth to find that Professor X's old foe the Shadow King has risen -and taken over Muir Island! It will take X-Factor and the X-Men's combined strength to triumph...and when the dust clears, the two teams will become one! An uncanny new era begins as the reunited X-Men go back to basics - beginning with a deadly confrontation with Magneto and his fanatical Acolytes! COLLECTING: VOL 19: X-MEN ANNUAL (1970) 15, X-FACTOR (1986) 65-70, UNCANNY X-MEN (1981) 278-280, X-MEN (1991) 1-3; MATERIAL FROM NEW MUTANTS ANNUAL 7, X-FACTOR ANNUAL 6