It is old X-Men versus new X-Men, and for the most part, the old X-Men seem to be winning, until Wolverine throws Marvel Girl a fatal blow, revealing her to be one of Lang’s X-Sentinels. Lang had created special Sentinels to take out the new X-Men team. His ultimate goal is the destruction of all mutantkind. Lang started working for the government, and slowly worked his way up, eventually gaining access to Larry Trask’s Sentinel files. With heavy financing, Lang managed to reboot the Sentinels and set out to destroy the X-Men.
Knowing that the old X-Men they are fighting are mechanical, the new X-Men attack with full force. While Lang is distracted, Cyclops breaks free from his holding tube and frees the others who are imprisoned. The X-Men want to bring Lang back to Earth to “stand trial for [his] crimes”. In retaliation, Lang sets the space station to self-destruct. Him and his goons escape, leaving the X-Men onboard.
They hurry back to the shuttle they arrived in, but Dr Corbeau breaks the bad news to the X-Men: the computer onboard the craft is broken, leaving them with only the choice of a manual re-entry. But given the immense solar flare, Corbeau (the only person who knows how to operate the craft) won’t survive the trip without being in the shielded “Life Cell” and while the craft runs on autopilot.
Jean steps in as Corbeau’s alternative (after telepathically absorbing his knowledge of piloting the shuttle), much to Cyclops’ disapproval. She proceeds to knock him out with a telekinetic blow. Jean convinces the rest of the X-Men that she is their best chance of survival. She starts the shuttle as the rest are sealed into the “Life Cell”.
Within mere minutes, Jean finds herself fighting against the solar flare for her life. Cyclops awakens and realises that the shuttle has flown into the flare with Jean piloting it. Colossus and Nightcrawler hold him down as he fights to get out of the cell to save Jean.
In her dying moments, Jean’s cries are answered by the entity known as the Phoenix Force. It offers to save her, but at a price of immense power that might consume her. Jean agrees to the bargain and merges with the Phoenix. But part of her soul still lingers in her old body, and out of compassion, the Phoenix seals it in a cocoon to heal, as a “second chance, in case things go wrong”.
Jean and the Phoenix are now one.
(Classic X-Men #8 is a reprint of Uncanny X-Men (Vol 1) #100.)