Though you made short work of the Vex on the Moon, it will all be for naught if the source of the incursions is left untended. Eris has found a way into their staging grounds in the Black Garden, but she must keep her attention fixed on the mysterious Pyramid for now. She asks that you and Ikora attend to this threat in her stead. Your investigation begins at the source, in the Black Garden.
Descend into the Black Garden and complete the Vex Offensive activity.