Digger Harkness

Digger Harkness, also known as Captain Boomerang, is a killer in Starling City.

Biography
As a man walked in an alley, Digger approached him and threw his boomerang, killing the man.

Trivia

 * The DC Comics character he is based on is named George Harkness, as "Digger" was his nickname. Harkness debuted in Flash #117 (December, 1960).