Uncanny X-Men #142

"Days of Future Past" concludes, and the text on the front cover says it all: "This issue: Everybody dies!" In the present day, the X-Men - with the help of the time-traveling Kate Pryde - face off against the newly reconstituted Brotherhood of Evil Mutants in a bid to save the life of pivotal anti-mutant politician, Senator Robert Kelly! And in the dark future from which Kate hails, the few remaining mutants mount a last stand against the robotic Sentinels to stave off nuclear Armageddon! This ultimate time-travel saga established the nightmarish tomorrow awaiting the X-Men and inspired generations of creators to continue challenging the future of Marvel's mutants! It's one of the all-time great Marvel comic books, boldly re-presented in its original form, ads and all! Reprinting UNCANNY X-MEN (1981) #142.