"The Origin of Professor X!" July 1965
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Stupefying Story by" Stan Lee
"Spectacular Layouts by" Jack Kirby
"Slam-Bang Pencilling by" Alex Toth
"Sensational Inking by": Vince Colletta
Plot: As Cerebro warns of an approaching menace of phenomenal power, the X-Men work to fortify the mansion. As the mysterious menace easily surpasses one defense after another, Professor X tells the X-Men of his childhood and his bullying step-brother Cain, who grows up to discover the Ruby Gem of Cyttorak, granting him the power of a Juggernaut. It is, of course, Cain, empowered as the Juggernaut, who is now bearing down on the X-Men, and after overcoming the final defense, easily wipes the floor with the X-Men themselves before coming face to face with Xavier.
