X-Men Milestones Reading Order

The Dark Phoenix Saga(By: John Byrne,Chris Claremont,Glynis Wein,Terry Kevin Austin)

1983

The Fall of the Mutants(By: Marc Silvestri,Chris Claremont,Louise Simonson,Walter Simonson)

2002

Messiah Complex(By: Peter David,Ed Brubaker,Craig Kyle)

2008

Mutant Massacre(By: Ann Nocenti,Chris Claremont,Louise Simonson,Walter Simonson)

2010

Necrosha(By: Zeb Wells,Craig Kyle,Christopher Yost)

2012

Second Coming

2010

Age of X

2011

X-Tinction Agenda(By: Chris Claremont,Louise Simonson)

2011

X-Cutioner's Song(By: Peter David,Fabian Nicieza,Scott Lobdell)

2011

Inferno(By: Chris Claremont,Louise Simonson)

2019