Karla Sofen
fictional character in Marvel Comics
Dr. Karla Sofen (also known as Moonstone, Meteorite, and Ms. Marvel) is a villainess turned anti-heroine of the Marvel Comics universe who is a nemesis of Hulk and once disguised as Captain Marvel for a large amount of time, manipulating her allies. Like many other Marvel villains, she eventually redeemed herself and joined the Thunderbolts. She is the archenemy of Carol Danvers.
Moonstone is a former psychologist who got her powers from a fusion with a gravity stone designed by the alien Kree. The character has been depicted as both a supervillain and an anti-hero at various times in her publication history.
She was created by Marv Wolfman and the late Frank Robbins, and first appeared in Captain America #192 in September of 1975.