The Uncanny X-Men #151

A tearful Kitty Pryde storms away from the Xavier Institute, suitcase in hand, as the assembled X-Men — Colossus, Storm, Wolverine, Professor X, and Nightcrawler among them — watch from the doorway behind her. The cover tagline, "The Day Kitty Pryde Leaves the X-Men, Is the Day the X-Men Fall!", sets up a genuinely gripping sense of loss and consequence, brought to life through Dave Cockrum and Joe Rubinstein's expressive linework. Chris Claremont's "X-Men Minus One!" promises the kind of emotionally charged mutant drama that made 1981 such a compelling era for this book.