In his very first work for Marvel in the U.S., iconic artist Alan Davis delivers on a double-sized NEW MUTANTS Annual that introduces Psylocke to the world of the X-Men! But she's arrived just as Sabretooth and the Marauders go on the hunt for Morlocks -- and they don't mind slaying any X-Men who get in the way! The "Mutant Massacre" event shocked readers and set a high-water mark for X-Men storytelling. Plus: Longshot joins the X-Men as they -- and the New Mutants -- take on Mojo in an Arthur Adams-drawn Annual! Meanwhile, Kitty Pryde is slowly disintegrating, leading the X-Men to make a deal with Doctor Doom to save her. Needless to say, the Fantastic Four have something to say about that! Collecting UNCANNY X-MEN (1981) #210-219, X-MEN ANNUAL (1970) #10, NEW MUTANTS ANNUAL #2 and FANTASTIC FOUR VS. X-MEN #1-4.