Phantom Girl is Tinya Wazzo, a member of the Legion of Super-Heroes in the 30th Century. Born on the planet Bgztl, she has the natural ability to become intangible and phase through objects. It has been implied that Bgztl is part of the Phantom Zone. Her romantic partner and later husband is Ultra Boy. During her brief time in the 20th Century, she became a member of L.E.G.I.O.N. named Phase.
In Reboot Legion continuity, Tinya uses the name Apparition. This version has a child with Ultra Boy named Cub Nah. Phase is explained as her long-lost Carggite duplicate. In Prime Legion continuity, Tinya is still Phantom Girl and her planet occupies the same space as Earth in another dimension. In the Prime Earth continuity, Linnya Wazzo is the new Phantom Girl.
The New 52