Changeling is an alias used by several characters in the DC Universe. Primarily it was a name taken by the super-hero vigilante Beast Boy, formerly of the Doom Patrol, when he grew tired of his original codename, having been mocked by the villain Arsenal. During his time as Changeling, Logan was a member of the Teen Titans. Eventually, he returned to his original Beast Boy alias.
Logan's Changeling identity was created by Marv Wolfman and George Perez, first appearing in DC Comics Presents #26 (1980).