Luna Maximoff was born to Pietro Maximoff and Crystal of the Inhumans. She stayed there on the moon with her mother's race.
Luna longed to go to Earth and see the ocean. After House of M|M Day, her father was taken to the moon to heal after a suicide attempt. Quicksilver stole the Terrigen Mists and convinced Luna to flee with him to Earth. Luna agreed, and went with Quicksilver to the ocean. There, she was exposed to the Terrigen Mists, and granted powers. With Quicksilver, they laid low for a while. Traveling to Genosha, Quicksilver granted various mutants their powers with the Mists. When Callisto's powers returned, they went crazy and sent her comatose.
Hoping to prevent another incident like this, Magneto confronted Quicksilver and Luna and reprimanded them. Quicksilver grew angry and attacked Magneto, but Luna saved her grandfather. Not realizing what she was doing was wrong, Luna tried to turn off his emotions so that he would not be sad over losing his powers. Magneto stopped her, and promised to leave if Quicksilver took care of her.