Regan is the daughter of the original Mastermind. Originally an agent for the Hellfire Club, she joined the X-Men after being captured by Pandemic. Shortly after, she betrayed the X-Men and joined the Marauders and eventually the Sisterhood of Mutants.

Lady Mastermind

Regan is the daughter of the original Mastermind. Originally an agent for the Hellfire Club, she joined the X-Men after being captured by Pandemic. Shortly after, she betrayed the X-Men and joined the Marauders and eventually the Sisterhood of Mutants.

All data from the awesome folks at Marvel.