New X-Men Vol. 6: Planet X
Grant Morrison (Writer), Phil Jimenez (Artist)
The X-Men thought he was dead. But the team's greatest adversary was simply in hiding, waiting in secret deep cover to make a move against the team that has thwarted his ambitions again and again. But where he was hiding will shatter the lives of everyone at Xavier's Mansion, if they even survive his latest attack. Plus: Wolverine discovers more secrets about his mysterious past and Jean Grey moves dangerously close to being consumed by the all-powerful Phoenix Force.
New X-Men #146-150