Moonstone aka Meteorite aka Ms. Marvel (real name Dr. Karla Sofen) is a fictional character, both a supervillain and superhero in Marvel Comics' Marvel Universe.
The character first appeared as a gun moll of the villain Dr. Faustus in Captain America (vol. 1) #192. She later appeared in issue #228 of The Incredible Hulk where it was revealed that she was the psychiatrist of the former Moonstone Lloyd Bloch and had tricked him into stealing relinquishing the moonstone to her. She was later revealed as a member of the shadowy organization known as the Corporation.
She appeared in Avengers as part of the supervillain team the Masters of Evil. During the disappearance of the Avengers and the Fantastic Four (after the Onslaught crossover), the Masters of Evil, Moonstone (as "Meteorite") included, posed as the Thunderbolts. After 12 issues, their identities were revealed.
Moonstone was one of the Thunderbolts' characters that Brian Michael Bendis moved over to the Dark Avengers, where she takes on the identity of Ms. Marvel and she becomes the main character in the Ms. Marvel solo title in issue #38.
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