This miniseries starts on Scott and Jean’s honeymoon. Rachel Summers–their daughter–brings their consciousnesses forward in time to her future, dystopic timeline (i.e., Days of Future Past), where Apocalypse is king.
While there, they find Nathan, their son, who in “real” timeline was raised in the future without them before returning to their time period as Cable.
In this future timeline, Rachel is known as Mother Askani. She tried to save Nathan Summer by cloning him and letting Apocalypse raise the clone (thinking it was the real Cable), and that kid grew up as Stryfe.
Cyclops and Phoenix, then, could raise the real Cable baby.
Confused yet?
It gets worse.
Nathan is the child of Scott and Madelyne Pryor, who was a clone of Jean Grey. So Jean spends her honeymoon raising another woman’s baby.
To protect their identities from Apocalypse (and I guess to protect their own timeline), they called themselves Slym and Redd. And of course they end up being freedom fighters.
The miniseries spans 12 years, which means we watch Cable grow older…
Nathan is a pariah for having the Legacy virus, which is highly contagious and deadly.
At the end of it, Apocalypse attempts to shift his soul into the body of Stryfe but Stryfe’s body can’t handle it because it is a clone, and Apocalypse dies in the process. w]When Mother Askani also dies, her ability to keep Jean and Scott in the future dies with her.
Since this is all an alternate future timeline, only the characters who travel back to the 616 are tagged as “real” characters.
This timeline is continued in 1995’s Askani’son limited series.
I don’t love all the timetravel in X-Men books, but this is really, really well done.