Evie Artino was the baby sister to Nova Artino. In the epilogue of Supernova, she is implied to be Magpie, who was rescued by Tsunami and brought to Renegades Headquarters after she was shot as her powers emerged.
When Evie was an infant she had fevers a lot, and because of that Evie's father had trouble putting her to sleep. He let her older sister, Nova, handle it as she has the ability to put people to sleep by touch. Later that night, Evie was shot at and presumptively murdered by the Roaches along with her mother and father.
Maggie is first caught by Adrian Everhart after stealing Nova's bracelet at the parade, which he makes her return. She is later seen in the training hall. She also delivers a message to Adrian from the council.
She is called to clean up after the attack with Hawthorn.
In Nova's attempt to get her bracelet back, it is revealed that Magpie keeps a bullet in her pocket. When Nova seems to mock it, calling it junk, Magpie screams at her and gets defensive of it, snatching it back. In the epilogue, it is revealed that Magpie got her powers after she was shot as a baby though her two parents were killed. Her older sister is said to have survived the attack, though her location is never revealed. It is heavily implied that Nova is that older sister, though it hasn't been confirmed.