Frost is appointed by Norman Osborn to lead his new team of "Dark X-Men". Each member is hand-picked by Norman but Frost has Namor added to the team for her own reasons. The team debuts to the public as the official "X-Men" maintaining high public approval through Osborn's careful media strategy. They oust the original X-Men, portraying them as a dangerous militia. Meanwhile, Frost discovers that Osborn is working with the Dark Beast, torturing apprehended mutants and feeding their powers into a machine that empowers Weapon Omega. Cyclops sends X-Force on a strategic evacuation of the mutant prisoners, resulting in a planned confrontation with the Dark X-Men. As the teams prepare to face off, Frost then reveals her role as a double agent, defeating the Dark X-Men with Namor's assistance. She extends an invitation to Cloak and Dagger to join the true X-Men as they teleport to the newly created island base Utopia. Upon learning of this, Norman orders his Dark Avengers and Dark X-Men to go after Frost, Namor, and Scott. During the final battle, Frost distracts the godlike Sentry by separating the Void persona from his Bob Reynolds persona. Doing so allows the Sentry to regain control and flee the battle, however, Frost cannot contain the Void and it chases after the Sentry, though a sliver of it remains within her body. Frost is forced to remain in Diamond Form in order to prevent the sliver of the Void from utilizing her omega level psychic abilities. Eventually it came to the decision to extract the Void. With Professor X's aid, they bridged Cyclops' mind to Frost. However, the Void instead took over his body, only for Scott to contain it within an inescapable prison in his mind.