UNCANNY X-MEN (1963) #100

The X-Men battle what appears to be their predecessors until Wolverine discerns the truth and, to the shock of his teammates, disembowels Marvel Girl to reveal her to be a robot. Lang bemoans the defeat of his X-Sentinels before recounting the origins of Project Armageddon to his captives, giving Cyclops time to escape Lang’s Nega-Tube and free the others. Lang boards a one-man flying gunship and attacks Cyclops while the other X-Men dispatch the rest of the X-Sentinels. Marvel Girl manipulates the gunship’s control, causing it to spin out of control. Ironically, Lang pleads with the X-Men for help before the gunship crashes ans explodes, seemingly killing him.…