Best Issue Ever!
When people ask me what my favorite X-Men story of all time is, my response is Days of Future Past. I remember when X-Men #141 came out and after seeing the cover wondering what gimmick Marvel was pulling. There's no way all of these X-Men are "slain" (yet they are). Even after reading it (and #142) the skeptic might assume that as part of an alternate timeline, this tale was nothing but a "what if" yarn. That skeptic couldn't have been more wrong. DOFP is a game changer, setting in motion a significant tonal change for the X-Men. So much goes back to this story. It's also the first appearance of Rachel. A thrilling read with perfect pacing and balance between present and future.