Disambiguation: Shadow Lass / Umbra
First published in: 1968
Tasmia Mallor first appeared as Shadow Lass in Adventure Comics (DC, 1938 series) #365 (February 1968). She first appeared as Umbra in Legionnaires (DC, 1993 series) #43 (December 1996).
See also the Adult Legion Shadow Woman.
Link: https://en.wikipedia.org/wiki/Shadow_Lass