From Cassius Comics

Originally a high society social club founded in the 1760s (with an American branch opening a decade later), the Hellfire Clubs has always been covertly led by an Inner Circle with aspirations of world domination. The Inner Circle was taken over by mutants close to a decade ago, and the club itself has changed to focus on mutant clientelle.

The Inner Circle

A cadre of would-be world conquerors that secretly runs The Hellfire Club, the Inner Circle has been dominated by mutants for nearly a decade. The members of the Inner Circle are most often given codenames corresponding to chess pieces.

Current and former members of the Inner Circle include the Black Bishop, Sebastian Shaw and Blackheart as Black Kings, Phoenix and Selene as Black Queens, the Black Rook, Elias Bogan, Edward Buckman, Magneto as the Grey King, the Hellions, Ms. Hoo, Benazir Kaur, Benedict Kine, Lord Imperial, Reeva Payge, Oliver Ryland, Paris Seville, Shinobi Shaw, Tessa (Sage), the White Bishop, Buckman, Magneto and Donald Pierce as White Kings and Hellstorm as an unofficial fourth one, Emma Frost and Saturnyne as White Queens, and the White Rook.