During a battle between the Avengers and the X-Men on the moon with the Phoenix Force fast approaching, Iron Man came up with a possible way of defeating the Phoenix Force. Iron Man used a suit specially designed for the task but instead of destroying the Phoenix it was split into five parts. Each part took a different X-Man as a host: Cyclops, Emma Frost, Colossus, Magik and Namor.
The Phoenix Five was created by Matt Fraction for the Avengers Vs. X-Men event comic book.
To begin with, the Phoenix Five used their powers to change the earth to create a peaceful and advanced place to live. Many struggling areas were given the climates needed to sustain themselves and Utopia underwent major changes. They provided free, clean and nigh unlimited energy to everyone and banned the use of weapons.
As the fight continued however, the Five showed continuous signs of corruption such as Namor's invasion of Wakanda and when Emma Frost murdered someone who had accidentally killed a mutant years before.
Major Story Arcs
Avengers Vs. X-Men
The Avengers were wary of the great power of the Phoenix Five and decided to create a strike force to capture Hope in case the Five went too far. After a brief confrontation the Avengers managed to escape with Hope after Scarlett Witch aided them. In retaliation the Five declared the Avengers to be enemies and started to hunt them down.
When Namor discovered the Avengers were hiding in Wakanda he lead an army of Atlanteans against the country. After much destruction the Avengers were able to defeat Namor just as the rest of the Phoenix Five arrived. As Namor lay on the floor his portion of the Phoenix entered the others taking Namor back to his previous levels of power while improving the rest. The Avengers narrowly escaped by entering a portal to K'un-Lun.
During the ensuing fights between the Avengers and the X-Men, the Phoenix Five were successful in capturing a lot of the Avengers, including Thor. The Avengers decided to reclaim their comrades but in doing so, Spider-Man was trapped in Limbo with Colossus and Magik. Spider-Man managed to manipulate the siblings into attacking each other to gain the other's portion of power. With Colossus and Magik eliminated, only Cyclops and Emma remained as hosts of the Phoenix.
After Emma discovered that the Avengers were hiding in K'un Lun using her vast telepathic powers, Cyclops attacked hoping to recapture Hope. The Avengers threw everything they had against Cyclops including a mystical dragon that had defeated the Phoenix force years before. Unfortunately for the Avengers, the dragon was not yet powerful enough to defeat the Phoenix and was beaten. After it seemed that Cyclops was going to succeed in his mission, Hope somehow managed to harness the power of the dragon and Scarlett Witch to get rid of Cyclops, sending him to the moon where he was severely injured.
Realizing he needed more power, Cyclops rushed to Emma in Utopia to keep the whole of the Phoenix Force in one place. There he found that Emma had been almost entirely corrupted by the Phoenix, attempting to convince him to completely destroy the world and remake it in their own image.
At that moment, the last remaining Phoenix Avatars were attacked by the combined might of the Avengers and the X-men while simultaneously attacked by Professor Charles Xavier on the astral plane. The combined assault was too much for the divided Phoenix Force and Scott, in his desperation, attacked Emma. Taking her portion of the Phoenix Force, he became the sole Phoenix Avatar, putting an end to the Phoenix Five.
Marvel: Avengers Alliance
The Phoenix Five appear in the third Special Operation for the Facebook game designed by Playdom, Marvel: Avengers Alliance. The player has the option of playing either the X-Men or Avengers side of the Avengers vs X-Men conflict. The storyline is different however to Avengers versus X-Men. A notable change is that the members of the Phoenix Five in the game are different with Jean Grey taking Namor's place. The reward for completing this Special Operation is getting Magik as a playable character.