Mockingbird is the code name

Code name

A code name or cryptonym is a word or name used clandestinely to refer to another name or word. Code names are often used for military purposes, or in espionage...

 of several characters in the DC Comics Universe

DC Universe

The DC Universe is the shared universe where most of the comic stories published by DC Comics take place. The fictional characters Superman, Batman and Wonder Woman are well-known superheroes from this universe. Note that in context, "DC Universe" is usually used to refer to the main DC continuity...

, denoting whoever is in charge of the Secret Six

Secret Six (comics)

The Secret Six is the name of three different fictional comic book teams in the , plus an alternate universe's fourth team. Each team has had six members, led by a mysterious figure named Mockingbird, whom the characters assume to be one of the other five members.-Original Secret Six:The Secret Six...

. The original Mockingbird's identity was unrevealed in the original series, but later identified as August Durant. The first Mockingbird of the villainous Secret Six was revealed to be Lex Luthor

Lex Luthor

Lex Luthor is a fictional character, a supervillain who appears in comic books published by DC Comics, and the archenemy of Superman, although given his high status as a supervillain, he has also come into conflict with Batman and other superheroes in the DC Universe. Created by Jerry Siegel and...

. After he gave up on the team, they worked independently until a new Mockingbird appeared giving them missions. Although its identity is unknown to the Six, it was revealed to be Amanda Waller

Amanda Waller

Dr. Amanda Blake Waller is a character published by DC Comics. She first appeared in Legends #1 in 1986, and was created by John Ostrander, Len Wein, and John Byrne...

.