The X-Men recreated in the image of Norman Osborn for the purpose of controlling the public image of mutant/human relations during Osborn's Dark Reign. This team was handpicked by Norman Osborn except for one member who was placed on the team as Emma Frost's spy. Emma will lead the team. Emma was forced to contend with all the members Osborn chose, but he allowed her to also add members. She chose just one: Namor, the Sub-Mariner, King of Atlantis, and mutant. Mystique is not an active field member, but merely necessary for PR purposes - imitating Professor X.
Cloak and Dagger are here presented with a chance to have their reputations exonerated and their records sealed if they join the Dark X-Men. Osborn presents it to them as the ultimate public service, where they can work off their past indiscretions - such as Cloak's dealings with the Avengers during the Skrull Invasion. Osborn chose Dagger mostly because of her healing power and the fact that she would certainly bring Cloak to the team with her.
Michael Pointer a.k.a. Weapon Omega can absorb and blast energy - a fact that could bring advantage to the team.
Daken/Dark Wolverine was chosen by Osborn to work as a gateway brand between the Dark Avengers and the Dark X-Men.
Mimic being dead and alive again was picked by Osborn because of his potential.
Besides the current roster: Emma Frost, Namor, Wolverine (Daken), Mimic, Cloak, Dagger and Michael Pointer, Dark Beast was also offered the job. Norman Osborn found this Dark Beast and offered him to stop experimenting on humans and start experimenting on mutants - building the Omega Machine.This caught Dark Beast's eye.
Major Story Arcs
After the events of Utopia, the remaining members of the Dark X-Men are Mystique, Dark Beast, Mimic, and Michael Pointer, who has chosen to be renamed Omega as opposed to Weapon Omega. Daken has either left the team or doesn't have enough time to be in both Dark Avengers and Dark X-Men.
After an event in a small town where a number of residents were slipping into trances and calling themselves X-Men, Norman Osborn sent his X-Men to investigate. The Dark X-Men started questioning one of the men who had slipped into the trance, when Mimic started having visions of his future and Omega suddenly started absorbing energy from the man. Whilst they both flew off as a result of the energy, some astral energy came out of the man and revealed itself to be Nate Grey, aka X-Man.
X-Man then attacked Dark Beast, but was fooled by Mystique into thinking that she was Jean Grey. As Nate talked to her, he started to run out of psychic energy, and returned to the astral plane. The Dark X-Men then went back to Norman Osborn, who after listening to their story, told them that he wanted Nate Grey captured for him and put into the Omega machine. The Dark X-Men managed to get Nate back to the physical world by going to H.A.M.M.E.R.'s Psi Division, which had the appearance of a cult. Although the Dark X-Men were able to convince the head psychic, Dr. Jarl, to search the astral plane for Nate, Nate used the link with Jarl to absorb all of the energy out of HAMMER's Psi Division, regain physical form and find out what he'd missed whilst he was "dead".
Finding out that Norman Osborn was responsible for what the world had become, Nate broke into Avengers Tower to kill Osborn, only to be confronted by the Dark Avengers. The Dark X-Men came in in the middle of this fight, and stood on the sidelines, unsure what to do. However, as Bullseye was about to kill Nate, Mimic took him out with an optic laser, as his orders had been to take Nate alive. Nate then temporarily took Mimic to plank time ("the time between time") and told Mimic that he and the rest of the Dark X-Men were "like a chaotic pinball machine", and that they were important to his plans. Shortly after this, Nate was seemingly killed in a psychic explosion. When Mystique went to Norman Osborn, she revealed that Nate was hiding inside Osborn's body.
After giving Nate some requests she wanted, Nate denied them, as he said that since he was in Osborn's body, he'd start changing the world back to how it should be. Unfortunately, Osborn's will was too strong, and he started losing control. Meanwhile, since Nate had denied Mystique's requests, Mystique decided to get the Dark X-Men and go into Osborn's mind, get Nate out, and be left off the team by Osborn. The team then used H.A.M.M.E.R.'s Psi Division once more, only this time they entered Osborn's mind. Little did they know that this was part of Nate's plans, as they unwittingly unlocked the Green Goblin persona from Norman Osborn's mind.
The Green Goblin attacked the Dark X-Men, before realising that he had to help Norman fight off Nate. The Goblin managed to do this by using Osborn's will to increase Mimic and Omega's powers so that they absorbed Nate's psychic energy, kicking him out of Osborn's mind. Before being taken away to be put in the Omega machine, Nate started to tell the Dark X-Men that they could've done good if they'd chosen to be heroes, before being cut off by Osborn and taken away. As he was taken away, the Dark X-Men realised that they should have helped Nate.