This lineup is best understood as the central cast of a period, with the changes left visible rather than smoothed into a permanent seven-person photograph.

This lineup is best understood as the central cast of a period, with the changes left visible rather than smoothed into a permanent seven-person photograph. 1978, #113–114: the aftermath of Magneto's Antarctic base splits the group. Phoenix and Beast reach the outside world believing the others have died; Scott's team survives elsewhere and believes Jean and Hank were lost. The separation produces months of different journeys, grief and missed information. A missing character in this stretch hasn't necessarily resigned. 1979, #119: Banshee damages his vocal cords stopping Moses Magnum. This is the injury that ends his reliable use of the sonic scream. He remains involved with his friends afterward, so injury and departure should be recorded separately. 1979, #125–126: Beast finds the surviving X-Men at the mansion in #125, and Scott's telephone call to Muir Island restores contact. The face-to-face reunion with Jean follows in #126, immediately tangled up with the Proteus emergency. The family gets remarkably little time to enjoy discovering that it hasn't already been broken. 1980, #129: Sean chooses to remain on Muir Island with Moira. Xavier is back at the school. Kitty Pryde enters the story as a prospective student, but she does not belong in the opening #101 lineup. 1980, #137–138: Phoenix is lost on the moon in #137. Jean's funeral and Scott's departure follow in #138. Beast and Angel participate in the closing crisis without becoming members of the initial Phoenix-era snapshot retroactively. Those final departures change both the practical roster and the emotional center of the book. The next team will inherit a functioning home, established friendships and an absence nobody can fill by simply putting on another costume.