Death in comics is pretty much a universally impermanent concept. But a death usually lasts a good while before the character comes back, with a couple exceptions.
Well, Marvel's X-Men editor Mark Paniccia has thrown out a teaser that another character who died very recently may be back sooner rather than later.
— Mark Paniccia (@MarkPaniccia) May 8, 2017
Jamie Madrox aka Multiple Man died at the very start of Death of X, the event that preceded Inhumans vs X-men which brought us to the ResurrXion branding that has seen both X-Men and Inhumans properties taking new directions. Well, apparently we may see this resurrection taken literally with Madrox's return. Funnily enough, all the series' had writer Charles Soule involved.
I never said he wasn't… https://t.co/z85PT8cpD3
— Mark Paniccia (@MarkPaniccia) May 9, 2017
Of course, we also know that the big bad of Astonishing X-Men is the Shadow King, a telepathic parasite that revels in illusions and nightmares, and previously teased artwork from Mike Deodato, the artist of the second issue, implied a 'stage play' involving X-Men characters, which could be a mental illusion or, hell, maybe someone in the Marvel Universe has actually decided to put on a play about the X-Men. Maybe it's a musical.
— axel alonso (@axelalonsomarv) May 3, 2017
At any rate, this could potentially be a tease for the characters return or just a tease, period. But fans of X-Factor and Madrox may want to pick up Astonishing X-Men #2 to find out.
[UPDATE] Updated with corrections with thanks to eagle-eyed continuity buff @quizlacey