X-Men: Days of Future Present

In this 1991 Marvel one-shot, writer Louise Simonson and artists Chris Wozniak and Terry Shoemaker bridge the original "Days of Future Past" storyline with a new generation of X-Men. The issue weaves together the present-day team with the time-displaced original X-Men, exploring the consequences of altering history. While a single issue, it stands as a key connective chapter in the franchise's sprawling timeline.