Nightwing

Nightwing. An alternate identity employed by Superman on those occasions when he and Jimmy Olsen, employing the name Flamebird, participate in adventures together inside the bottle city of Kandor.

The Prussian blue color of Superman's Nightwing costume is reminiscent of the plumage of the nightwing, a Kandorian bird. Superman and Jimmy Olsen first adlpt their Nightwing and Flamebird identities during an adventure in Kandor in January 1963 (S No. 158: "Superman in Kandor" pts. 1-III; "Invasion of the Mystery Super-Men!"; "The Dynamic Duo of Kandor!"; "The City of Super-People!"). They employ them again during a second adventure, in August 1964 (WF No. 143: "The Feud Between Batman and Superman!" pts. 1-II -- no title; "The Manhunters from Earth!").