Regan Wyngarde is the daughter of Jason Wyngarde, a.k.a. the late mutant terrorist Mastermind. She is also presumed to be the sister of a woman calling herself Mastermind, Martinique Jason, also a mutant criminal, who is known to have been involved in superhuman conflicts in London and Paris, and who has adopted the codename Mastermind after Jason Wyngarde's death. The efficiency of Wyngarde's mutation in combat situations much depends on the element of surprise, and her abilities have no effect on mechanical units and detectors. While this limits Wyngarde's direct aggressive capabilities, she is not to be underestimated. Wyngarde, who is presumed to earn her keep as a mercenary, was recently seen as an associate of Sebastian Shaw in Sydney, Australia, where the pair were involved in an assault on the X-Men.

Recently Wyngarde was discovered comatose in a lab that was being used for illicit mutant experimentation. She has since recovered and been recruited by Rogue for her X-Men mutant rapid reaction force. Wyngarde recently betrayed the X-Men to the mutant villains known as the Marauders. She has since joined the team.

Regan was apparently killed by Wolverine during a battle between the X-Men and the Marauders.