Hear me, X-Men! No longer am I the woman you knew! I am fire! And life incarnate! Now and forever -- I am PHOENIX! 
Solicit Synopsis
The greatest comic-book saga ever told, in one cosmic-sized Omnibus! It begins with a shocking story in which Marvel Girl sacrifices herself...only to be reborn as Phoenix! But when a galaxy-spanning adventure reveals that Jean Grey has somehow attained power beyond conception, Cyclops and the X-Men can only watch as Phoenix is corrupted, absolutely. As the team faces the Shi’ar Empire, Hellfire Club and more, can Jean Grey be redeemed? Chris Claremont, Dave Cockrum and John Byrne weave an epic tale of triumph and tragedy that changed everything for the X-Men — and all of comics! It’s the full Dark Phoenix Saga, with bonus tales illuminating Jean Grey’s defining story!
This issue collects following issues:
X-Men #97
"My Brother, My Enemy!"
"My Brother, My Enemy!"
X-Men #98
"Merry Christmas, X-Men — The Sentinels Have Returned!"
"Merry Christmas, X-Men — The Sentinels Have Returned!"
X-Men #99
"Deathstar, Rising!"
"Deathstar, Rising!"
X-Men #100
"Greater Love Hath No X-Man..."
"Greater Love Hath No X-Man..."
X-Men #101
"Like a Phoenix, from the Ashes"
"Like a Phoenix, from the Ashes"
X-Men #102
"Who Will Stop the Juggernaut?"
"Who Will Stop the Juggernaut?"
X-Men #103
"The Fall of the Tower"
"The Fall of the Tower"
X-Men #104
"The Gentleman's Name is Magneto"
"The Gentleman's Name is Magneto"
X-Men #105
"Phoenix Unleashed!"
"Phoenix Unleashed!"
X-Men #107
"Where No X-Man Has Gone Before!"
"Where No X-Man Has Gone Before!"
X-Men #108
"Armageddon Now"
"Armageddon Now"
X-Men #125
"There's Something Awful on Muir Island!"
"There's Something Awful on Muir Island!"
X-Men #126
"How Sharper Than a Serpent's Tooth...!"
"How Sharper Than a Serpent's Tooth...!"
X-Men #127
"The Quality of Hatred!"
"The Quality of Hatred!"
X-Men #128
"The Action of the Tiger!"
"The Action of the Tiger!"
X-Men #129
"God Spare the Child..."
"God Spare the Child..."
X-Men #130
"Dazzler"
"Dazzler"
X-Men #131
"Run for Your Life!"
"Run for Your Life!"
X-Men #132
"And Hellfire is Their Name!"
"And Hellfire is Their Name!"
X-Men #133
"Wolverine: Alone!"
"Wolverine: Alone!"
X-Men #134
"Too Late, the Heroes!"
"Too Late, the Heroes!"
X-Men #135
"Dark Phoenix"
"Dark Phoenix"
X-Men #136
"Child of Light and Darkness!"
"Child of Light and Darkness!"
X-Men #137
"The Fate of the Phoenix!"
"The Fate of the Phoenix!"
X-Men #138
"Elegy"
"Elegy"
Phoenix: The Untold Story #1
"The Fate of the Phoenix!"
"The Fate of the Phoenix!"
Classic X-Men #6
"A Love Story"
"A Love Story"
Classic X-Men #8
"Phoenix"
"Phoenix"
Classic X-Men #13
"Lifesigns"
"Lifesigns"
Classic X-Men #18
"Stalking Life!"
"Stalking Life!"
Classic X-Men #24
"Vacation"
"Vacation"
Classic X-Men #43
"Flights of Angels"
"Flights of Angels"
Bizarre Adventures #27
"Compiled from the Files of Professor X X-Men Data Log Phoenix"
"Compiled from the Files of Professor X X-Men Data Log Phoenix"
What If? #27
"What If the Phoenix Had Not Died?"
"What If the Phoenix Had Not Died?"
Notes
This was later reprinted as Phoenix Omnibus #1