UNCANNY X-MEN (1963) #457

The world’s end! Brief Description: While Psylocke waits imprisoned in the X-plane and has a strange encounter with her mad brother on the Astral Plane, the X-Men are ambushed and do battle with a band of costumed humanoid dinosaurs. The dinosaurs use their superhuman abilities to usurp Rachel’s mind causing her to think she is a dino-mutant. Rachel turns her telepathy against her teammates and helps the dinosaurs defeat the team. The X-Men are taken captive and carried through a glowing portal.…